Colombo, March 30:

Battles between government forces and Tamil Tiger rebels killed 28 insurgents and

four soldiers across northern Sri Lanka, the military said today.

Air force fighter jets bombed a base of the Sea Tigers — the rebels’ naval wing — in the guerrilla-held northern district of Mullaitivu, said military spokesman Brig Udaya Nanayakkara. He gave no details of casualties or damage, but said pilots confirmed hitting the target.

The battles and airstrikes were part of a heavy increase in fighting in the country’s civil war in recent months. The government has vowed to crush the rebels by the end of the year, but diplomats and other observers say the army is facing more resistance than it expected.

Army troops fought separate gunbattles in the northern Wanni region yesterday that killed 15 Tamil rebels and one soldier, Nanayakkara said. In the northeastern Welioya region, a clash left three soldiers and one rebel dead, he said.

Also yesterday, army troops destroyed two Tamil Tiger bunkers and killed 10 rebels in the Mannar district, while two more rebels were killed in Jaffna peninsula.