"One of the pilots was found, he is safe and sound. The search is still ongoing," he said.

According to the French news channel BFMTV, the pilot of one of the two aircraft ejected before the collision, while the instructor and student pilot who were in the second were still missing.

The local prefecture said that the search and rescue operation are being carried out with the French army. "The military authorities will communicate on the causes of the accident," it said in a press release, Xinhua news agency reported.