PARIS/CAIRO (AFP, REUTERS) - Smoke was detected inside an EgyptAir plane shortly before it plunged into the Mediterranean with 66 people on board, investigators said Saturday (May 21), offering clues but no answers as to why it crashed.
The Airbus A320 had been flying from Paris to Cairo early Thursday when it plummeted and turned full circle before vanishing from radar screens, without its crew sending a distress signal.
France's aviation safety agency said Flight MS804 had transmitted automated messages indicating smoke in the cabin as the disaster unfolded.
One aviation source said that a fire on board would likely have generated multiple warning signals, while a sudden explosion may not have generated any - though officials stress that no scenario, including explosion, is being ruled out.
Egypt said its navy had found human remains, wreckage and the personal belongings of passengers floating in the Mediterranean about 290 km north of Alexandria.
While the information may help investigators, more wreckage including the black boxes will need to be found before they can piece together what happened.
"There were ACARS messages emitted by the plane indicating that there was smoke in the cabin shortly before data transmission broke off," a spokesman for France's Bureau of Investigations and Analysis told AFP.
It was "far too soon to interpret and understand the cause of the accident as long as we have not found the wreckage or the flight data recorders", he said.
ACARS - Aircraft Communications Addressing and Reporting System - transmits short messages between aircraft and ground stations.
Search teams were scouring the eastern Mediterranean Saturday for more parts of the plane and the black boxes.
While Egypt's aviation minister has pointed to terrorism as more likely than technical failure, French Foreign Minister Jean-Marc Ayrault said Saturday that nothing was being ruled out.
"At this time... all theories are being examined and none is favoured," he told a news conference in Paris.
The disaster comes just seven months after the bombing of a Russian airliner over Egypt's Sinai peninsula in October that killed all 224 people on board.
In the wake of that incident foreign governments issued travel warnings for Egypt and demanded a review of security at its airports after the Islamic State group said it had downed the plane with a bomb concealed in a soda can.
The Islamic State group was quick to claim responsibility for that attack, but there has been no such claim linked to the EgyptAir crash.
A French patrol boat carrying equipment capable of tracing the black boxes was expected on Sunday or Monday.
The plane disappeared between the Greek island of Karpathos and the Egyptian coast in the early hours of Thursday.
It had turned sharply twice before plunging 22,000 feet (6,700 metres) and vanishing from radar screens, said Greek Defence Minister Panos Kammenos.
The passengers were 30 Egyptians, 15 French citizens, two Iraqis, two Canadians, and citizens from Algeria, Belgium, Britain, Chad, Portugal, Saudi Arabia and Sudan. They included a boy and two babies.
Seven crew and three security personnel were also on board.
EgyptAir Chairman Safwat Moslem said the radius of the search zone was 40 nautical miles, but could be expanded. The radius is equivalent to an area of 5,000 square miles (17,000 square km), the same expanse covered in the initial hunt for the Air France jet in 2009.
The large area reflects the fact that neither jet could be accounted for in the last few minutes of flying time.
The European Space Agency said one of its satellites on Thursday spotted an oil slick about 40km southeast of the plane's last known location.
Moslem told AFP on Saturday the priority was finding the passengers' remains and the flight recorders, which will stop emitting a signal in a month when the batteries run out.
"The families want the bodies. That is what concerns us. The army is working on this. This is what we are focusing on," he said.
Relatives of the passengers gathered at a hotel near Cairo airport on Friday after meeting airline officials as they struggled to come to terms with the catastrophe.
"They haven't died yet. No one knows. We're asking for God's mercy," said a woman in her 50s whose daughter had been on board.
But on Saturday, a funeral service was held at a church in Cairo for 26-year-old EgyptAir hostess Yara Hany Farag, who was on Flight MS804.
In a hall inside the church compound decorated with flowers, a picture of a smiling Yara was placed on a cross covered entirely with white flowers: the young woman was engaged and expecting to be married in the coming months.