Two Indian Air Force fighter jets crashed Saturday, killing one pilot and injuring two others, in an apparent mid-air collision while on exercises south of New Delhi.

The crash is the latest in a string of military aircraft accidents at a time when the government is trying to modernise its armed forces and meet India's complex security challenges.

It involved a Russian-made Sukhoi Su-30, carrying two pilots, and a French-built Mirage 2000, operated by a third, and was reported by witnesses to police at around 10 am.

Both aircraft took off from the Gwalior air base, around 50 km east of where they came down.

"The aircraft were on routine operational flying training mission," the country's air force said in a statement, adding that one of the three pilots was fatally injured.

An investigation was underway to determine the cause of the crash, it added.

The first plane hit the ground in the forests of Pahadgarh in central Madhya Pradesh state, around 300 km south of New Delhi.

"Two pilots were found near the crash site, who were later evacuated in an IAF chopper for treatment," Morena district police superintendent Ashutosh Bagri told AFP.

"Both of them are out of danger," he added.

The second jet crashed some distance away in Rajasthan state, and images from local rescue authorities showed military officials inspecting mechanical wreckage strewn across the ground.