Four of five bodies of India Army personnel were found after after a military helicopter crashed near the Tuting town of Arunachal Pradesh on Friday.

The Indian Army said that efforts are underway to recover the fifth body.

“The cause of the crash at this stage is not known,” the Army said in a statement. “Details are being ascertained.”

The crash took place near the Migging village, which is located 25 kilometres away from Tuting in the Upper Siang district. The helicopter was an Advanced Light Helicopter.

The public relations office of the defence department at Guwahati said that the helicopter had taken off from Likabali town in the Lower Siang district. Two Army Advanced Light Helicopters and one Indian Air Force Mi-17 aircraft were deployed for search and rescue operations.

The site where the helicopter crashed is not connected by road, authorities said.

On October 5, an Indian Army pilot, Lieutenant Colonel Saurabh Yadav, died after his Cheetah helicopter crashed in Arunachal Pradesh’s Tawang district during a routine sortie.