French investigators suspect that a fire alarm on board a departing El Al Boeing 737-900ER was triggered by a lithium battery installed on a wheelchair.

The alert occurred on 27 October as the aircraft (4X-EHE) was preparing to operate from Paris Charles de Gaulle to Tel Aviv.

Investigation authority BEA says the aircraft had started rolling from the P1 apron and TA1 taxiway adjacent to Terminal 2A.

“The crew used the fire extinguishers in the cargo hold,” says the authority, after an alarm in the hold had been activated.

Passengers were disembarked via stairs. BEA says the source of the alarm “seems to be” a wheelchair with a lithium battery.

None of the occupants of the aircraft was injured.