Conflicting reports and accounts emerged about whether the wreckage of the EgyptAir flight MS804 has been found off a Greek island.
A Greek military official said an Egyptian search plane has located two orange objects believed to be from the missing plane.
The official says the objects were found 230 miles (370 kilometres) southeast of the island of Crete, but still within the Egyptian air traffic control area.
One of the objects was oblong, said the official, who spoke on condition of anonymity in accordance with regulations, according to AP.
Egypt has also confirmed the Greek statement, with the aviation ministry saying that floating objects and pieces of plastic as well as lifejackets have also been found near the island of Karpathos.
However, later on Thursday, Senior Greek air safety official said debris found so far in Mediterranean does not belong to an aircraft, according to AFP.
The flight left Paris at 11:09pm GMT and was due to land at Cairo International Airport at 03:15am local time.
The last contact between the flight and the air traffic tower was at 2:30am Cairo time, while radar signals were lost at 2:40am.
Egyptian civil aviation minister Sherif Fathy said at a noon press conference on Thursday that the cause of the incident has not been determined, and that the possibilities of a terrorist attack or a technical malfunction have not been ruled out.
Fathy also said that Egypt will cooperate with French authorities to investigate the disappearance of the plane.
Who was on board?
EgyptAir said that 66 people were on board; 56 passengers –including three children – and 10 crew members, three of whom were security personnel.
According to Egypt's civil aviation minister, the flight was carrying 30 Egyptians, 15 French, two Iraqis, one Briton, one Canadian, one Sudanese, one Chadian, one Portuguese, one Algerian, one Belgian, one Kuwaiti and one Saudi.
Egypt's Prosecutor-General Nabil Sadek has ordered an investigation into the incident, according to a prosecution statement.
The civil aviation minister said that Egypt will cooperate with French authorities in a joint investigate into the disappearance of the plane.
French President Francois Hollande stressed that no hypothesis on the reason behind the crash should be ruled out.
The director of Greece's Civil Aviation Authority says air traffic controllers were in contact with the pilot of the EgyptAir flight as it passed through Greek airspace.
The director, Constantine Lyzerakos, said the plane was at 37,000 feet, travelling at 519 mph, and did not report any problem.
Lyzerakos told Antenna television that controllers tried to make contact with the pilot 10 miles before the flight exited the Greek Flight Information Range (FIR), but the pilot did not respond.
Lyzerakos says controllers continued trying to contact the pilot until 3:39am Greek time (12:39 GMT) when the plane disappeared from the radar.
He said the plane was in Egypt’s FIR when it vanished.
Timeline of the flight
Greece's civil aviation department released a timeline on the flight’s route and Greek attempts to contact it.
02:24 EgyptAir flight 804 from Paris to Cairo enters Greek airspace, air traffic controller gives permission for the remainder of its course.
02:48 The flight is transferred to the next air traffic control sector and is cleared for exit from Greek airspace. “The pilot was in good spirits and thanked the controller in Greek.”
03:27 Athens air traffic control tries to contact the aircraft to convey information on the switch of communications and control from Athens to Cairo air traffic. In spite of repeated calls, the aircraft does not respond, whereupon the air traffic controller calls the distress frequency, without a response from the aircraft.
03:29 It is above the exit point [from Greek airspace].
03:39:40 The aircraft signal is lost, approximately 7 nautical miles south/southeast of the KUMBI point, within Cairo FIR. Immediately the assistance of radars of the Hellenic Air Force is requested to detect the target, without result.
03:45 The processes of search and rescue are initiated, simultaneously informing the Flight Information Region of Cairo.
Greece deployed military aircraft and a frigate to the southern Mediterranean where the aircraft vanished, its defence ministry said.
According to AP, the French military says a Falcon surveillance jet monitoring the Mediterranean for migrants has been dispatched to help search for the flight.
Military spokesman Col. Gilles Jaron told AP that the jet is joining the Egypt-led search effort, and the French navy may send another plane and a ship to the zone.
He said the Falcon was on a surveillance mission as part of EU efforts to monitor migrants crossing the Mediterranean for Europe.
Egypt hosts families of passengers
Egypt’s civil aviation minister said authorities are hosting the relatives of passengers who were on the plane.
"We immediately thought we should contact the families of the passengers, and we are hosting them at the airport here in Cairo and also at Paris' Charles De Gaulle," said Fathy.
He also said that families who are currently in France will be granted free tickets to Egypt so they are able to closely follow the matter.