Wreckage of EgyptAir flight MS804 has been found south of the Greek island of Karpathos, Egyptian aviation officials confirmed.
The Airbus A320 was en route from Paris to Cairo with 66 passengers and crew when it went down overnight.
Egyptian Vice-President Ahmed Adel told CNN the rescue operation was “turning into a search and recovery”.
Officials say the plane is more likely to have been brought down by a terrorist act than a technical fault.
It made two sharp turns and dropped more than 25,000ft (7,620m) before plunging into the Mediterranean Sea, Greek Defence Minister Panos Kammenos told reporters.
“There have been finds south-east of Crete, inside the Cairo flight information area,” Greek army general staff spokesman Vassilis Beletsiotis told AFP news agency.
The search in seas south of the Greek island of Karpathos involves Greek and Egyptian naval forces, and the British Royal Air Force.
Sixty-six people were on board Flight MS804, most of them from Egypt and France. A Briton was among the passengers.
Of those on the plane, 56 were passengers, seven were crew members and three were security personnel.
Greek aviation officials say air traffic controllers spoke to the pilot when he entered Greek airspace and everything appeared normal.
They tried to contact him again at 02:27 Cairo time, as the plane was set to enter Egyptian airspace, but “despite repeated calls, the aircraft did not respond”. Two minutes later it vanished from radar.
Kammenos said: “The picture we have at the moment on the accident as it emerges from the Greek air force operations centre is that the aircraft was approximately 10-15 miles inside the Egyptian FIR [flight information region] and at an altitude of 37,000 feet.
“It turned 90 degrees left and then a 360-degree turn toward the right, dropping from 37,000 to 15,000 feet and then it was lost at about 10,000 feet.”
Egyptian Aviation Minister Sherif Fathi said: “Let’s not try to jump to the side that is trying to identify this as a technical failure – on the contrary.
“If you analyse the situation properly, the possibility of having a different action, or having a terror attack, is higher than the possibility of having a technical [fault].”
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