Teams from Australia, Malaysia and China working together to find an airliner which disappeared three years ago say they have called off their search.
The Press Association reported today that authorities hunting for Malaysia Airlines flight MH370, which disappeared with 239 people on board, had taken the decision with "sadness", after they scoured more than 46,000 square miles of ocean.
Very little is known about what happened to the airliner when it disappeared after it sent its last transmission at 1.19am on 8 March 2014. But here's what authorities have managed to figure out:
It didn't send out a distress signal
MH370's pilots made their last communication with air traffic control less than an hour after it took off from Kuala Lumpur International Airport, at 12.41am. But it wasn't a distress signal - instead, the pilot or co-pilot bade air traffic controllers goodnight just before 1.20am. A few minutes later, the plane's communication system was shut down as it crossed into Vietnamese airspace.
It kept flying for hours
Thai military radar picked up MH370 south of Phuket, just after 2.20am, and the plane sent out seven "handshakes" - automatic communications with the ground - at hourly intervals until 8.11am.
The flight, from Kuala Lumpur to Beijing, should have taken five and a half hours - but the plane was tracked for seven hours and 38 minutes.
It crashed somewhere in the Indian Ocean
Although the 46,000 square mile search area has yielded few clues as to what happened, seven pieces of debris have been found, according to the BBC, with one discovered on the French island of Reunion, just off Madagascar, and one found on a sandbank in Mozambique.
At one point, the search area was expanded to nearly 3m square miles - about 1.5 per cent of the Earth's surface.
There was probably a sudden electrical failure
Reports suggest the plane's Satellite Data Unit unexpectedly tried to "log on" to a satellite half an hour after it took off, which suggests its electrical systems may have suddenly shut down sometime during a 56-minute window after its final scheduled transmission, a report from the Australian Transport Bureau suggested.
The Daily Beast reported that makes it highly unlikely the crash was due to pilot action - more likely, it was a devastating fire in the cargo hold.
The disappearance was unlikely to have been terrorism-related
Among the 227 passengers were people from China, Malaysia, the US, Canada, Indonesia, Australia, India, France, New Zealand, Ukraine, Russia and Iran. Although one line of questioning focused on two Iranian men who were using false passports, they didn't have any links with terrorist groups.