PARIS, May 20 (Xinhua) -- A helicopter of the French gendarmerie crashed Friday afternoon in Cauterets, Hautes-Pyrenees,in southwest France, killing four gendarmes on board, Le Figaro reported Friday, citing a gendarmerie source.

According to a senior official of the gendarmerie, the accident took place shortly before noon during a mission in Cauterets.

The helicopter, which hit a cliff during the mission, belonged to the gendarmerie of Tarbes.

The reason of the accident has not been determined yet, the gendarmerie source said.