Two military helicopters have collided during a training sortie over India's western state of Gujarat on Thursday, killing nine air force personnel, the government has said.

Television pictures showed the burnt out remains of the Russian-made MI-17 multi-utility helicopters in what seemed like a sparsely populated area.

The wreckage was surrounded by police, firefighters and military officials.

Officials quoted by the media said the crash site was a military area near the Jamnagar airbase in Gujarat, a state bordering Pakistan. No casualties or loss of property on the ground was reported.

The military has been plagued by several fatal accidents, often due to obsolete hardware. More than half of the 872 MiG fighters India bought from Moscow since the early 1960s have crashed.

India plans to spend about $100bn over the next 10 years to upgrade the largely Soviet-era military equipment.