US aviation regulators allowed Boeing's 737 Max aircraft to continue flying despite knowing there was a risk of further crashes.
Analysis after the first crash last year predicted there could be up to 15 disasters over the lifetime of the aircraft without design changes.
Despite this, the Federal Aviation Administration did not ground the Max until a second crash five months later.
FAA chief Steve Dickson, who started in August, said this was a mistake.
The FAA risk assessment was revealed during a US congressional hearing on Wednesday. Lawmakers are investigating Boeing following fatal 737 Max crashes in Indonesia in October 2018, and Ethiopia in March. The disasters killed 346 people in total.
Air safety officials investigating the crashes have identified an automated control system in the 737 Max 8, known as MCAS, as a factor in both accidents.
Boeing has said the system, which relied on a single sensor, received erroneous data, which led it to override pilot commands and push the aircraft downwards.
What went wrong in Boeing's cockpit?
The FAA's investigation of the October Indonesia crash called for Boeing to redesign its system, warning of a risk of more than a dozen crashes over the 45-year lifetime of the roughly 4,800 737 Max planes in service.
Regulators also issued an alert to airlines, but the agency did not ground the aircraft until after the 10 March Ethiopia crash, several days after action by other countries.
"Was a mistake made?" asked Democrat congressman Henry Johnson.
"Obviously the result was not satisfactory," said Mr Dickson. In response to later questions, he admitted the agency had made a mistake at some point in the process.
'Grave concerns'
Boeing is revising the MCAS software, but lawmakers say their investigation has shown that the aircraft manufacturer was aware of flaws in the system.
Boeing staff have also raised concerns that the company was prioritising speed over safety at the factory that produced Max 737s, contributing to the crashes.
Ed Pierson, a former senior manager at the factory, told Congress he repeatedly warned Boeing's leadership of the safety risks caused by what he described as a "factory in chaos", but it had little effect.
He also said that, after the crashes, US government regulators have shown little interest in his concerns.
"I remain gravely concerned that... the flying public will remain at risk unless this unstable production environment is rigorously investigated and closely monitored by regulators on an ongoing basis," he said in prepared testimony.
Mr Dickson said the FAA is probing production issues. He also said he is considering further actions against Boeing.
In a statement, Boeing said Mr Pierson's own account showed the company took his concerns seriously.
"Company executives and senior leaders on the 737 programme were made aware of Mr Pierson's concerns, discussed them in detail, and took appropriate steps to assess them," it said.
A US House of Representatives panel is expected to approve impeachment charges against President Donald Trump later in a marathon session of rancorous debate.
The judiciary committee is debating two articles of impeachment alleging abuse of power and obstruction of Congress.
A full vote by the Democratic-run House next week will likely make him the third US president ever impeached.
But the Senate, controlled by Mr Trump's fellow Republicans, is not expected to remove him from office.
"No crime!" the US president said on Twitter early on Thursday.
What do the articles of impeachment say?
Mr Trump is accused of trying to force Ukraine to launch a corruption investigation into his political rival Joe Biden, a leading Democratic contender for the White House next year; and obstruction of Congress for stonewalling the House investigation.
The Democrats who run the committee have agreed the language of the nine pages detailing the charges, saying that Mr Trump "betrayed the nation" by acting "corruptly".
There are 41 members on the panel, which is expected to vote along party lines on Thursday afternoon local time.
Republicans are trying to introduce amendments, but unified Democrats on the panel are rebuffing such proposed changes
What is being said in the debate?
The judiciary committee launched the two-day session on Wednesday evening at the Capitol.
Republicans decried the impeachment case as "hot garbage", while one Democrat accused the president of a "constitutional crime spree".
Jim Jordan, an Ohio Republican, said Democrats were only impeaching Mr Trump because "they don't like the 63 million people who voted for this president, all of us in flyover country, all of us common folk".
But Democrats rebuked Republicans for their loyalty to Trump.
"Wake up!" said Representative David Cicilline, accusing the other party of "wilfully ignoring the facts to protect a corrupt and dangerous president".
A SIMPLE GUIDE: If you want a basic take, this one's for you
GO DEEPER: Here's a 100, 300 and 800-word summary of the story
WHAT'S IMPEACHMENT? A political process to remove a president
VIEW FROM TRUMP COUNTRY: Hear from residents of a West Virginia town
CONTEXT: Why Ukraine matters to the US
FACT-CHECK: Did Ukraine interfere in the 2016 election to help Clinton?
What will happen next week in the House?
A handful of Democrats in swing districts remain unsure how they will vote on impeachment when it comes to next week's debate.
But Democrats have a 36-seat lead over Republicans in the House so passage is still expected to go ahead.
Democrats stepped back from including in the impeachment charges findings by Special Counsel Robert Mueller that Mr Trump may have obstructed the justice department's inquiry into alleged Russian election meddling.
The party's lawmakers from more conservative districts have argued the focus should be limited to Ukraine.
Democratic leader Nancy Pelosi said on Thursday they would not whip the historic vote, allowing members to make their own personal choice.
What will happen in the Senate?
The Senate is expected to hold a trial next month on the charges and acquit the president.
Republicans who hold sway in the chamber appear to favour a quick vote, limiting political fanfare.
Mr Trump has indicated he would like to see witnesses called such as Joe Biden and his son, Hunter, who worked for a Ukrainian gas firm that the US president wanted investigated.
Mitch McConnell, the Senate majority leader, said on Wednesday no decision had yet been made over how to conduct the trial.
Analysts say the 100-seat chamber does not have the 67 votes needed to remove Mr Trump from office.
Whiffs of fragrant roses, jasmine and bergamot are rising from the flask.
"You smell those flowery tones? These are the basis of all women's perfume," says Guy Delforge, spraying a bottle of his own creation.
From his workshop in the citadel perched above the Belgian city of Namur, he ingredients from around the world to craft his signature scents.
A perfumer for 34 years, Mr Delforge, 78, notes a shift in the industry with customers pushing for natural, sustainable fragrances.
"Perfumes have existed for 5,000 years and the scents haven't changed much," he says.
"But today... customers want to know the artisan making their perfume. It reminds me of when I started selling perfume from my garage in the 1980s."
Millennials are the driving force behind the trends reshaping the sector, according to beauty industry magazine Cosmetics Business. It says they want more transparency and more gender-neutral scents - often based on citrus smells.
Citrus is one of the seven families of smells; with floral, chypre (oak moss with fruity notes), and amber often regarded as female scents, while fougère (lavender/woody) woody and leather are often grouped as male scents.
"A person is born liking one specific scent family and that preference rarely changes," says Mr Delforge, whose eponymous line carries 40 eau de parfums, with each 100ml bottle costing €51 ($57; £45).
In the heart of Namur's old city, Romain Pantoustier, "le nez" or nose in French, provides customers with transparency about the ingredients used in his perfumes.
The glass bottles of his Nez Zen range are refillable, the perfumes are gender neutral and also vegan, avoiding the musks from deer and other animal-derived produce were used in the past. Deer musk is specifically a secretion produced from the scent gland of the male musk deer.
An international convention covers the trade in musk but most products in the perfume industry now contain synthetic versions of the previously used animal scents. This is the one area where millennials definitely prefer synthetic ingredients instead of natural ones in their perfumes.
In the past other animal-derived ingredients used in perfume included ambergris from sperm whales, produced by the mammal's digestive system, and castoreum - a secretion made by beavers.
Synthetic versions of lily of the valley - one of the world's most expensive flowers - are also available. Such use of synthetics can also make products more cost effective, but often make use of petroleum and its by-products.
Mr Pantoustier, 40, says nature is the basis of his inspiration. He quizzes each customer on their favourite colours, textures, feelings and hobbies before recommending a fragrance. He also designs tailor-made perfumes for individual clients for €1,500.
"When a person comes in I ask them what they like. I use words to create a mapping in my head to guide them through my fragrances," he says, while drinking water flavoured with an edible scent. "Who am I to say what gender a scent should have?"
The Frenchman founded the Belgium-based business in August 2016 with his wife Aurélie, after working as a scent designer for some of Europe's biggest perfumers.
"I wanted to move away from a more industrial approach to perfuming, and get back to a much more artistic and emotional approach."
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Across the Atlantic, Charna Ethier also used to work for large firms in the fragrance sector, before founding the Providence Perfume Company in 2009.
"I noticed there was a demand for natural botanical smells that was being neglected," she says. "There's lots of greenwashing in the sector."
Inspired by her childhood on a farm on the US east coast, she says many modern shoppers are so used to synthetic smells in perfumes they do not know what natural options smell like.
Ms Ethier, 44, distils fruits, flowers, wood and plants in a pure alcohol spirits base to create her natural perfume line. Providence Perfume's website says the final products contain no synthetics, petrochemicals, fragrance oils, dyes, parabens, phthalates or chemical fragrances.
All her perfumes are also gender neutral, something she says is particularly appreciated by her younger clientele.
"Millennials don't want to wear their mom's perfume. They want to smell different, like leather, crushed herbs and smoke," she explains. "I get a lot of women saying they don't want to smell like flowers."
Gender fluid fragrances have surged in popularity in recent years: 51% of all perfume launches in 2018 were gender neutral, up from 17% in 2010, according to industry figures.
At Coty, the world's largest fragrance firm, with 77 brands including Chloé, Hugo Boss and Gucci, trends for more gender fluid, sustainable and exclusive products are closely monitored.
"The companies who are winning are the industry leaders that have refreshed their proposition, and new brands because millennials are brand agnostics," says Laurence Lienhard, Coty's vice president of consumer marketing insights.
Ms Lienhard says Coty has also worked hard over the past five years to use less packaging and more organic ingredients.
"It's time for bigger brands to take a stand - so we are working on it more and more.".
Ms Lienhard adds that demand for gender fluid, universal scents is particularly strong in English-speaking countries. It released its first unisex offering, Gucci Mémoire d'une Odeur, earlier in 2019. The scent is marketed in both men's and women's sections of perfume stores.
Back in Belgium, Mr Delforge peruses through the French Perfumers Society's official perfumes guide, which he calls "the bible" of perfumery.
"This book describes all the different scents, but two perfumers could choose the same ingredients and create a different smell. It is like different chefs making different types of mayonnaise. It's still mayonnaise but it doesn't taste the same," he explains. "Perfume is the same."
YouTube will no longer allow videos that "maliciously insult someone" based on "protected attributes" such as race, gender identity or sexuality.
The video-sharing platform will also ban "implied threats of violence" as part of its new harassment policy.
A row erupted in June after a prominent video-maker said he had been the target of abuse by another YouTube star.
At the time, YouTube said its rules had not been broken. But it has now deleted many of the videos in question.
"Even if a single video doesn't cross the line, with our new harassment policy we can take a pattern of behaviour into account for enforcement," Neal Mohan, chief product officer at YouTube, told the BBC.
As a result of the policy change, the Google-owned business also considered taking down clips of President Trump calling Democratic Senator Elizabeth Warren "Pocahontas" to taunt her over her claim that she has distant Native-American heritage.
But it decided that the president's intention was to curry favour with voters rather than attack his opponent on race and so the videos could remain online.
What was the row about?
At the centre of the dispute was journalist Carlos Maza, who presented videos for the Vox channel.
Mr Maza said he had been the subject of persistent abuse from rival video-maker Steven Crowder, who presents a talk show on YouTube.
Mr Crowder had about four million subscribers at the time, while Vox had about six million followers.
Mr Maza created a video compilation of all the times Mr Crowder had made fun of his sexual orientation and ethnicity.
In the clips, Mr Crowder imitated Mr Maza's accent and called him, among other things, a "lispy queer", a "gay Vox sprite" and a "gay Mexican".
Mr Crowder said the language he had used to mock Maza was "friendly ribbing".
But the videos led many of Mr Crowder's viewers to harass Mr Maza on social media.
YouTube said it had conducted an "in-depth review" and found "the videos as posted don't violate our policies".
However, it later restricted Mr Crowder's ability to earn advertising revenue due to "continued egregious actions".
On Wednesday, it was expected YouTube would delete several of Mr Crowder's videos that fell foul of its updated harassment policy. But it appears he made the material private in advance.
What does the updated policy say?
Prior to the change, YouTube had already banned videos that:
contained explicit threats of violence
bullied somebody about their appearance
revealed somebody's personal information
encouraged viewers to harass an individual
But the new policy also bans:
"veiled" or implied threats of violence, such as saying "you better watch out"
simulated violence towards an individual
malicious insults based on protected attributes such as race, gender expression or sexual orientation
YouTube said the new policy would apply to "everyone" including politicians and popular YouTube stars as well as the general public.
Video-makers who consistently break the rules will have their ability to earn advertising revenue restricted, and may have videos deleted or their channel closed.
The company said there would be some exemptions from the new policy, including insults used in "scripted satire, stand-up comedy, or music".
Mr Mohan told the BBC that individual complaints would have to be judged on a case-by-case basis, with the context of each video being taken into account.
However, the new guidelines do say: "This is not a free pass to harass someone and claim, 'I was joking.'"
Mr Mohan said YouTube had consulted with think tanks, video-makers, Google employees and other third parties to help inform its policy.
He told the BBC he did not think the new rules would restrict YouTubers' freedom of expression.
"We don't want YouTube to be a place where public discourse is getting stifled as a result of people having the fear of being harassed on our platform," he told the BBC.
"My view is that, on balance, having a strong framework around which we are protecting individuals from being harassed is important to ensure that our platform remains one where there can be robust debate."
The UK is going to the polls for the country's third general election in less than five years.
The contest, the first to be held in December in nearly 100 years, follows those in 2015 and 2017.
Polling stations in 650 constituencies across England, Wales, Scotland and Northern Ireland opened at 07:00 GMT.
After the polls close at 22:00 GMT, counting will begin straight away. Most results are due to be announced in the early hours of Friday morning.
A total of 650 MPs will be chosen under the first-past-the-post system used for general elections, in which the candidate who secures the most votes in each individual constituency is elected.
In 2017, Newcastle Central was the first constituency to declare, announcing its result about an hour after polls closed.
Elections in the UK traditionally take place every four or five years. But, in October, MPs voted for the second snap poll in as many years. It is the first winter election since 1974 and the first to take place in December since 1923.
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Anyone aged 18 or over is eligible to vote, as long as they are a British citizen or qualifying citizen of the Commonwealth or Republic of Ireland and have registered to vote. Registration closed on 26 November.
Details about where to vote can be found on the Electoral Commission website and are also listed on polling cards sent to households.
People do not need a polling card to be able to vote but will need to give their name and address at their local polling station. People can only vote for one candidate or their ballot paper will not be counted.
Prime Minister Boris Johnson has cast his vote - he visited a polling station in central London, taking his dog, Dilyn, along with him, and Labour leader Jeremy Corbyn posed for pictures when he went to vote in north London.
SNP leader Nicola Sturgeon visited a polling station in Glasgow, while Liberal Democrat leader Jo Swinson cast her vote at a polling station in East Dunbartonshire, accompanied by her husband Duncan Hames.
Plaid Cymru leader Adam Price voted in Carmarthenshire and Green Party co-leader Jonathan Bartley did so in south London.
Brexit Party leader Nigel Farage has used a postal vote.
Ahead of the poll, the elections watchdog has reminded voters that taking selfies and other photos inside polling stations is not permitted and may be a breach of the law.
Many people have already put a cross next to the name of their favoured candidate by voting by post - more than seven million people used a postal vote two years ago.
Those who applied for a postal vote but have yet to return it to their Electoral Office must do so by 22:00. Alternatively, they can hand it into their local polling station by the close of polls.
According to the BBC's weather forecast, Thursday will be a wet day in many parts of the country, with highs of five degrees Celsius in Edinburgh, nine in Cardiff, seven in Belfast and eight in London.
A 43-year-old man has been arrested in northern Brazil for dressing up as his mother to take her driving test.
When Heitor Schiave's 60-year-old mother, Maria, failed her test three times, the mechanic decided to step in.
Wearing a floral blouse and sporting painted nails, make-up and a wig, he drove around Nova Mutum Paraná and his plan appeared to be paying off as .
But suspicions were soon raised that the woman in the driving seat was not the woman on "her" ID.
Cat 'arrested' for break-in at Brazilian prison
"He tried to be as natural as possible. He wore lots of make-up with his nails nicely done and [wore] women's jewellery," instructor Aline Mendonça told G1.
The police were called and he was arrested at the driving school for fraud and misuse of someone's identity.
"He's already confessed. He confessed that he wasn't the woman in question but the son, her son who was trying to pass as his mum so that she would be able to pass this practical driving test," the instructor added.
Mr Schiave reportedly said that his mother did not know of the plan.
A painting discovered on the wall of an Indonesian cave has been found to be 44,000 years old.
The art appears to show a buffalo being hunted by part-human, part-animal creatures holding spears and possibly ropes. Some researchers think the scene could be the world's oldest-recorded story. The findings were presented in the journal Nature by archaeologists from Griffith University in Brisbane, Australia. Adam Brumm - an archaeologist at Griffith - first saw the pictures two years ago, after a colleague in Indonesia shimmied up a fig tree to reach the cave passage.
"These images appeared on my iPhone," said Mr Brumm. "I think I said the characteristic Australian four-letter word out very loud." The Indonesian drawing is not the oldest in the world. Last year, scientists said they found "humanity's oldest drawing" on a fragment of rock in South Africa, dated at 73,000 years old.
What do the drawings show?
The drawings were found in a cave called Leang Bulu'Sipong 4 in the south of Sulawesi, an Indonesian island east of Borneo. The panel is almost five metres wide and appears to show a type of buffalo called an anoa, plus wild pigs found on Sulawesi. Alongside them are smaller figures that look human - but also have animal features such as tails and snouts. In one section, an anoa is flanked by several figures holding spears.
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"I've never seen anything like this before," said Mr Brumm. "I mean, we've seen hundreds of rock art sites in this region - but we've never seen anything like a hunting scene." However, other researchers have questioned whether the panel represents a single story - and say it could be a series of images painted over a longer period. "Whether it's a scene is questionable," says Paul Pettitt, an archaeologist and rock-art specialist at Durham University told Nature.
How do we know it's 44,000 years old?
The team analysed calcite "popcorn" that had built up on the painting. Radioactive uranium in the mineral slowly decays into thorium, so the team measured the levels of different isotopes of these elements. They found the calcite on a pig began forming at least 43,900 years ago, and the deposits on two buffalo were at least 40,900 years old. There are at least 242 caves or shelters with ancient imagery in Sulawesi alone - and new sites are being discovered annually.
How does it compare to other prehistoric art?
It may not be the oldest drawing, but researchers say it could be the oldest story ever found. "Previously, rock art found in European sites dated to around 14,000 to 21,000 years old were considered to be the world's oldest clearly narrative artworks," said the paper in Nature. The Sulawesi drawings could also be the oldest animal drawing ever found. Last year, a cave painting in Borneo - thought to be the oldest of an animal - was found to be at least 40,000 years old.
New Zealand police have said they plan to recover bodies from White Island - where a volcanic eruption killed at least eight people - on Friday morning.
The recovery mission will go ahead despite the risk of another eruption, police said.
"Today is less safe than yesterday, and the day before that," volcanologist Dr Graham Leonard said.
At least eight people are thought to be on the island following the eruption on Monday. All are presumed dead.
Police said they were planning a "high-speed recovery" of the bodies.
Eight others have already been confirmed dead, and 20 are in intensive care after suffering burns when the volcano erupted as tourists were visiting.
GeoNet, New Zealand's geological hazard information site, said on Thursday there was a 50-60% chance of another eruption within the next 24 hours. But families of the victims are growing increasingly desperate for the bodies to be recovered. "We are now living with a growing sense of desperation to bring home those that we know are there," Whakatane Mayor Judy Turner told reporters. "The frustration of those families most affected is completely understandable."
New Zealand volcano: What we know of the victims
What's the recovery plan?
Deputy Police Commissioner Mike Clement told reporters on Thursday that officials had agreed a recovery plan even though the risk that the volcano will erupt had not diminished. "This is not a zero risk operation," he said. Eight specialists from the New Zealand Defence Force will go to the island on Friday morning and "make every effort to recover all bodies". Surveillance flights have allowed police to locate only six bodies so far. "We will make calls as the morning goes by," Mr Clement said. He added that his biggest concern was the unpredictable volcano, followed by the weather, the direction of the wind and the state of the sea. "A lot of things have to go right for this to work." The fast recovery will also mean there will be less time to collect the evidence needed to ensure that the bodies are properly identified. "It does come with trade-offs," Mr Clement said. Volcanologist Dr Leonard said the recovery mission could be dangerous. "Whakaari/White Island is an active volcano, and the estimated chance of an eruption is increasing every day," he said.
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Local Maori groups have placed a rahui over the waters around the volcano and the coastal stretch on the Bay of Plenty. It is a traditional prohibition restricting access to an area. White Island, called Whakaari by the Maori, holds spiritual significance for the local Ngati Awa tribe. The rahui was placed on Tuesday morning and will be lifted only once the missing bodies are recovered. An expert from the Ngati Awa will accompany authorities in the recovery mission. "Ngati Awa are front and centre of this operation so for the uplifting of the deceased, once that decision is made, Ngati Awa will be going across to Whakaari/White Island," deputy commissioner Wally Haumaha told RNZ. Rahui are often placed on areas after deaths or accidents occur or to protect natural resources in a specific area. They are not legally binding but are commonly respected by New Zealanders.
What state are the injured in?
The volcano erupted on Monday when at least 47 visitors from around the world were on the crater. Many of the survivors are still in intensive care. Some have been unable to identify themselves because their burns are so severe, police say. An estimated 120 sq m of replacement skin will be needed for all the patients, according to Dr Peter Watson from New Zealand's National Burns Unit. Surgeons in burns units around the country are working around the clock, authorities said. Some of the Australian victims have been flown back to their home country, and more are expected to follow in the coming days.
White Island is a popular tourist destination off the northern coast of North Island and there were day tours and scenic flights available.
