Two Indian radar technicians were wounded when Tamil Tigers staged an air attack on a strategic Sri lankan military base on Tuesday, but were chased by Air Force fighters, which for the first time shot down one of the planes.

The Tigers' air strike on the military base in Vavuniya came as part of a brazen counter-attack by the rebels that led to heavy fighting on the ground in which 22 people, including 10 soldiers and equal number of guerrillas were killed.

Sources said the two Indians, identified as Roop and Thakur, were carrying out maintenance and training of Sri Lankan personnel manning an Indian-supplied radar at the northern airbase.

The two were evacuated for treatment to Colombo, sources said. They were stated to be out of danger.

Indian High Commission officials said the two workers sustained minor injuries.

Air Defence radars picked up two LTTE [Images] light aircraft while they were approaching the Vavuniya area early Tuesday morning, Air Force spokesperson Wing Commander Janaka Nanayakkara said.

"One of the aircraft has been shot down in the Mullaitivu skies while running away following the failed mission," Nanayakkara said.

This is the first time that Sri Lankan fighters have been able to intercept an LTTE light aircraft.

The LTTE aircraft appeared to have been part of a massive ground attack launched by the rebels aimed at a complex of Sri Lankan air and land bases.