Shillong, Oct. 16 :    Shillong, Oct. 16:  Barely 72 hours after a MiG-21 crashed in Rajasthan, the air force today lost two more fighter jets and a pilot in a mid-air collision near the central Assam town of Tezpur. Senior air staff officer of the Eastern Air Command, Air Marshal M. MacMohan, said the two MiG-21s collided during a training session. 'It was a bad day for us. We lost two fighter jets and a skilled pilot. The other pilot sustained multiple injuries,' MacMohan added. The pilot killed in the crash was Squadron Leader Jodh Singh. 'He was from Chandigarh. We have informed his family about the tragedy. The other pilot is undergoing treatment at the military hospital in Tezpur,' MacMohan said. The collision took place 40 km west of Tezpur at 11 am, minutes after the two combat planes took off from the Salonibari airbase. MacMohan said it was yet to be ascertained whether pilot error or snags in either of the MiG-21 aircraft caused the mid-air mishap. 'We do not know what happened. The cause of the collision will be known only after experts conduct an inquiry,' he said. Air officer commanding-in-chief, Air Marshal K.N. Nair, was unavailable for comment. Sources said he was out of station. Today's crash was the 61st involving MiG aircraft since 1997. Some MiG-21 planes in the air force fleet are no less than 37 years old. Though referred to as 'flying coffins' in air force circles, there is no proposal to ground the ageing fleet of Russian fighter aircraft. Air Chief Marshal A.Y. Tipnis had said here recently that the fighter jets would be 'upgraded' for use till the end of this decade.