Pictures have been posted online showing debris from the EgyptAir jet that came down in the Mediterranean on Thursday.
The images show items from the stricken plane, including a child’s life jacket and what appears to be part of a seat.
Analysis of the debris is likely to be key to determining what happened to the flight.
The images were posted after it emerged the plane sent several warning signals about smoke detected in the jet before it crashed.
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.
Egypt said its navy had found human remains, wreckage and the personal belongings floating in the sea about 290 km (180 miles) north of Alexandria.
Search crews are scouring for further wreckage, especially the plane’s cockpit voice and flight data recorders, commonly known as black boxes.
Planes and vessels from Egypt and five other countries – Greece, Britain, France, the United States and Cyprus – are involved in the search.
The waters in the area are 8,000 to 10,000ft deep, and the pings from the black boxes can be detected up to a depth of 20,000ft.
The plane was carrying 66 passengers and crew when it crashed on Thursday.