Greek civil aviation sources say the EgyptAir flight MS804 that went missing early on Thursday crashed into the Mediterranean, AFP reports.

French officials, including President Francois Hollande, have also confirmed, with Hollande offering help in the search of debris.

There has been no official confirmation from the Egyptian side. EgyptAir has not commented on any particular report, but has denied "all misleading information published by news websites and social media channels regarding the reasons of the disappearance of EgyptAir flight MS804 and the company confirms that the reason of disappearance hasn't been yet confirmed."

According to AFP, the plane went into the sea some "130 nautical miles [around 240 km] off the island of Karpathos".

Earlier, EgyptAir announced it had received a distress signal from the Egyptian military, but the latter denied.

MS804, flying between Paris and Cairo, had 56 passengers and 10 crew on board.

A press conference of Egypt's Civil Aviation Minister Sherif Fathy is due later in the afternoon.