Full coverage: EgyptAir Flight MS804 Missing

PARIS, May 19 (Xinhua) -- French President Francois Hollande and his Egyptian counterpart, Abdel-Fattah al-Sisi, vowed on Thursday to "work closely to establish as soon as possible the circumstances of the disappearance" of Egyptair MS804, the Elysee said in a press release.

PARIS, May 19, 2016 (Xinhua) -- A policeman registers reporters at the counter of EgyptAir in Paris Charles de Gaulle Airport, France, May 19, 2016. A crisis center was set up early Thursday morning at Terminal 1 of Paris Charles de Gaulle airport for the missing EgyptAir MS804 flight, French media reported. The flight, an Airbus 320, disappeared from radar en route from Paris to Cairo early Thursday, the Egyptian airline confirmed. (Xinhua/Li Genxing)

The ill-fated plane disappeared from radar early Thursday morning en route from Paris to Cairo.

Speaking to local radio, French Prime Minister Manuel Valls said the French government is "in close contact with the Egyptian military and civil authorities."

"France is ready to participate in the searches," he said, adding that "no hypothesis can be excluded on the causes of the disappearance."

French Foreign Minister Jean-Marc Ayrault said his ministry and French Embassy in Cairo are fully mobilized to obtain all information related to the missing flight, an Airbus 320.

The plane was carrying 56 passengers, including one child, two infants, and 10 crew members, the Egyptian airline confirmed on its Twitter account.

The plane, which took off at 11:09 p.m. local time (2109 GMT), was flying at an altitude of 37,000 feet (11,280 meters) and was 10 miles (16 km) inside Egyptian airspace when losing contact with the radar at 2:45 a.m. Cairo time (0045 GMT), an official source in the airline said.

According to Egyptair, 15 French nationals were on board, along with 30 Egyptians, two Iraqis, one British, one Belgian, one Portuguese, one Algerian, one Chadian, one Saudi, one Kuwaiti, one Sudanese and one Canadian.

A toll-free number has been announced for friends and families of the passengers on board.