New Delhi, Oct 6 (PTI): An Mi-17 helicopter of the Indian Air Force crashed near Tawang in Arunachal Pradesh today, killing seven military personnel, a senior IAF official said.

Five IAF personnel, including two pilots, and two armymen were killed in the crash near the remote town of Tawang, close to the China border, around 6 am, the official said.

The Russian-manufactured Mi-17 V5 helicopter was carrying supplies to a forward post of the Indian Army in the mountainous region.

"A court of inquiry has been ordered to ascertain the cause of the accident," he said.

Earlier in the day, an IAF official had said five personnel were killed and one person was critically injured.

The crash comes a day ahead of Air Force Day, celebrated in a big way by the force.

"Our losses in the peacetime are a cause of concern. We are making concerted efforts to minimise accidents and preserve our assets," Air Chief Marshal B S Dhanoa had said yesterday, referring to a string of crashes of IAF choppers and military jets in recent years.

The Mi-17 V5 is a Russian built medium-lift military transport chopper.