Indian Air Force’s Mi- 17 V5 helicopters fly-past during a presentation in Jamnagar, on March 4, 2016.

:: An Indian military helicopter crashed in a disputed area near the border with China on Friday, killing all seven troops on board, the army said.

The Russian-made Mi-17 V5 helicopter was on a maintenance mission in the mountainous district of Tawang near the border with Tibet when it crashed.

Five Indian Air Force (IAF) crew members and two personnel of the Indian army were killed in the crash, a spokesman told AFP.

“A court of inquiry has been ordered to ascertain the cause of the accident,” he said. Tawang is in the northeast Indian state of Arunachal Pradesh, which is also claimed by China.

It is a strategically important border district and came briefly under Chinese control during the 1962 war between the two neighboring countries.

The Mi-17 V5, which is mainly used for military transport, is produced by Kazan Helicopters, a subsidiary of Russian Helicopters.

‘Flying coffins’

India’s Air Force has a high rate of crashes owing to its ageing fleet. More than 170 pilots have lost their lives over the last three decades. Most of the accidents involve Soviet-era MIG planes, earning them the sobriquet “flying coffins”.

In July an IAF chopper crashed in the same state, killing three crew members and a soldier. That advanced light helicopter was on a rescue mission during devastating floods when it crashed due to inclement weather.

Last year, a Russian-built AN-32 military transport plane went missing over the Bay of Bengal with 29 people on board. And in 2013, all 20 people on board an army helicopter were killed when it crashed in northern India.

India, the world’s largest arms importer, has been trying to revamp its ageing and outdated military aircraft, with some of the fleet virtually on its last legs.

The country has been trying to develop its own warplanes but delays and technical shortcomings have marred progress.