EgyptAir flight MS804: What we know so far
Since EgyptAir flight MS804 disappeared from radar at 2.26am local time on Thursday, there has been much speculation as to what caused the aircraft to crash into the Mediterranean.
Until the aircraft's black boxes are discovered, it remains impossible to say exactly what happened to the Airbus A320, but facts are emerging that are helping experts piece together the flight's final minutes.
The plane's final moments
Flight MS804 left Paris Charles de Gaulle airport at 23:09 local time (21:09 GMT) on Wednesday evening. Greek air traffic controllers made contact with the pilot at 23:48 GMT. They said that the pilot seemed relaxed and reported no problems.
At 00:27 GMT, just before the plane left Greek airspace, Greek air traffic controllers tried to make contact with the pilot, but there was no response despite multiple attempts.
At 00:29 GMT the aircraft left Greek airspace and seconds later vanished from Greek radar.
The plane lost contact with Egyptian radar at 00:30 GMT (02:30 Cairo time), when it was 280km (174 miles) from the Egyptian coast.
According to Greek officials, before the Airbus vanished from radar, it was flying at 38,000ft when it suddenly swerved 90 degrees left, before completing a 360 degree turn right, plummeting thousands of feet and disappearing from radar.
Who was on board
There were 66 people from 12 nationalities on board the doomed flight; 56 passengers and seven crew members and three Egyptian security staff.
Among the named victims was 40-year-old Welshman, Richard Osman, a geologist and father-two who is thought to have recently moved to Jersey.
Canadian media said one of the victims was Marwa Hamdy, an executive with IBM originally from the province of Saskatchewan, who had relocated to Cairo.
There were two babies and one child on board according to a statement by EgyptAir.
The plane and the pilots
Neither the pilot or the co-pilot have been named by EgyptAir, but the airline confirmed that the pilot had 6275 of flying hours including 2101 flying hours on Airbus 320 while the co-pilot had 2766 flying hours.
The aircraft was 13 years old.
There were fires onboard
Air industry website, the Aviation Herald, reported that the Aircraft Communications Addressing and Reporting System (ACARS) - which which downloads maintenance and fault data to an airline operator - confirmed that smoke detectors had gone off in the toilet and the aircraft's electronics before the signal was lost.
A spokesman for France's BEA air accident investigation agency said the signals did not indicate what caused the smoke or fire on board the plane.
The last ACARS message was at 00:29 GMT and the contact with the plane was lost four minutes later at 02:33 local time.
The search
Search and rescue operations began at 00:45 GMT.
Debris from the doomed aircraft, including shoes, life jackets, fabric from the seats and body parts has been discovered 180 miles of the Egyptian coast.
These articles could provide valuable clues as to what happened to the plane and are being tested for explosive residue. However, it remains impossible to know exactly what brought the plane down without the flight's black box and voice recorder.
Teams from France, Egypt, UK and forces from the American base in Sicily are scouring the Mediterranean for these vital parts as well as more wreckage from the plane.
Was it terrorism?
A terrorist attack was one of the earliest theories, but Egyptian investigators stress that it is too soon to make any judgment based on the information collected so far.
Was terrorism behind EgyptAir plane crash, or not?
Experts are assessing material from air traffic control, aircraft and crew documents and aircraft data management systems AIRMAN and ACARS and the French Foreign Minister Jean-Marc Ayrault, said there were several possible causes. "At this very moment all scenarios are being examined and none is being given greater emphasis," he said.