An Air Algerie flight from Burkina Faso to Algiers in northern Africa has disappeared from radar, the official Algerian news agency confirmed.
APS said air navigation services lost track of the plane 50 minutes after take-off in the early hours of this morning.
"In keeping with procedures, Air Algerie has launched its emergency plan," the agency quoted the airline as saying.
The flight path of Flight AH5017 from Ouagadougou, the capital of the west African nation of Burkina Faso, to Algiers was not immediately clear.
Ouagadougou is almost directly south of Algiers, passing over Mali where unrest continues in the north.