At least nine personnel of the Indian Air Force (IAF) lost their lives when two MI-17 helicopters collided over Sarmat village, about 10 km away from the coastal town of Jamnagar on Thursday.Defence spokesman Group Captain MG Mehta told Mail Today that the helicopters were on their routine training sortie when the accident took place.The multi-role helicopters are learnt to have been out on a practice for a bombing mission when the accident occurred. Each of the helicopters were learnt to have been carrying a pilot, a co-pilot and other crew members."There were nine personnel on board and all succumbed to injuries" said a statement from the Ministry of Defence. "The helicopters had taken off from Jamnagar airbase and were on a routine flying training mission," it added.Defence Minister AK Antony has expressed sorrow at the tragic incident and has conveyed his heartfelt condolences to the bereaved families.One of the helicopters caught fire after the accident in which the rotor of one chopper is said to have hit the other, said sources in Jamnagar."We can arrive at the definite reason for the accident only after an inquiry, which has already been initiated," Mehta told Mail Today. Meanwhile, sources maintained that such mid-air collision is a rare occurrence and in case there has been any deviation from the standard operating procedure, this could be a very serious breach of cockpit discipline.Some villagers who happened to be there said that the helicopters collided soon after they took off from the base.Although such collisions are rare, several MiG fighters had crashed in the vicinity in the last decade.Four people including two children had died and nine injured when a MiG-21 had crashed in Lakhabawal, about 20 km from Jamnagar on February, 2004. Another MiG-21 crashed during a firing exercise near Jamnagar on January, 2006, with the pilot ejecting safely. In June, 2006 another MiG-29 had crashed in the area. A MiG-29 jet had crashed near an airfield in Jamnagar in November 2006 while yet another MiG-29 crashed in September 2008.