The plane left Paris' Charles de Gaulle airport on Monday and traveled to Marseille and then Sanaa in Yemen before heading towards Moroni.
The aircraft — which was due to have landed in the capital of the Indian Ocean archipelago at 2300 GMT Monday — disappeared from radar screens, said the airport source.
A crisis task force was set up at Charles de Gaulle airport early Tuesday.
(Another Airbus A330 aircraft, crashed into the Atlantic Ocean between Brazil and France on June 1 with 228 people on board. There were no survivors.)
Other sources confirm the plane crashed.