Officials with the airline and the Egyptian civil aviation department told Reuters they believed the Airbus A320 had crashed into the sea.
Egypt Air said the plane sent an emergency signal – possibly from an emergency beacon attached to the plane – at 04:26 a.m., two hours after it disappeared from radar screens.
In water crashes, an underwater locator beacon attached to the aircraft’s flight recorders starts to emit a signal or ping. This helps the search and rescue teams to locate the boxes, and the location of the crash.
The aircraft was carrying 56 passengers, including one child and two infants, and 10 crew, EgyptAir said. They included 30 Egyptian and 15 French nationals, along with nationals from 10 other countries.
Greek air traffic controllers spoke to the pilot over the island of Kea, in what was thought to be the last broadcast from the aircraft.
“The pilot did not mention any problems,” Kostas Litzerakis, the head of Greece’s civil aviation department, told Reuters.
However, during the transfer to Cairo airspace, Greek controllers were unable to reach the pilot and the plane vanished from their radars shortly after leaving Greek airspace, he added.
Greece said it had deployed aircraft and a frigate to the area to help with the search.
A Greek defense ministry source said authorities were also investigating an account from the captain of a merchant ship who reported a ‘flame in the sky’ some 130 nautical miles south of the island of Karpathos.
French President Francois Hollande’s office said the French leader had just spoken to his Egyptian counterpart and that both sides would cooperate closely.
Under U.N. aviation rules, Egypt will automatically lead an investigation into the accident assisted by countries including France, if it is confirmed that an Airbus jet was involved.
It should be recalled that Russia’s Metrojet Airbus A321 crashed in the Sinai on October 31, 2015, killing all 224 people on board. Russia and Western governments have said the plane was likely brought down by a bomb, and the Islamic State militant group said it had smuggled an explosive device on board.
In March, an EgyptAir plane flying from Alexandria to Cairo was hijacked and forced to land in Cyprus by a man with what authorities said was a fake suicide belt. He was arrested after giving himself up.