Fierce fighting broke out between government troops and separatist Tamil Tiger rebels in northern Sri Lanka on Monday leaving 30 guerrillas dead, an official said.

The battle occurred when the Tigers tried to attack a defense line in Mullikulam village of northern Vavuniya district, military spokesman Brig. Udaya Nanayakkara said.

"Ground troops have confirmed that 30 Tigers have been killed, we have recovered five bodies," he said.

Rebel spokesman Rasiah Ilanthirayan could not be reached for comment and the military's claims could not be independently verified.