Ferocious battles raged in Sri Lanka's embattled north over the weekend as security forces tried to break into territory held by Tamil rebels, the two sides said on Sunday.
Government forces smashed through a bunker line of the Liberation Tigers of Tamil Eelam (LTTE) inflicting heavy casualties on the rebels, the defence ministry said.
It raised the number of guerrillas killed in fighting since Saturday morning to 22 from the earlier figure of 15. The ministry said military losses also doubled to four dead on Saturday.
But the guerrillas said they resisted the military push and inflicted heavy losses on government forces.
The pro-rebel Puthinam.com website said the Tigers had killed 55 troops and wounded another 120 in Saturday's fighting.
The heavy fighting erupted on Saturday, hours after the Tigers sank a navy fast attack craft off the island's northeastern coast, leaving 10 sailors missing believed dead.
Sri Lankan war planes bombed suspected Tamil Tiger facilities Saturday inside the area they control in the north of the island, the defence ministry said, adding that there were no immediate reports of casualties.
The government claims it has killed 2,264 rebels since January against the loss of 135 of its own troops. The government allows no journalists or rights groups into the embattled regions, making it impossible to verify the figures.
Thousands of people have been killed in a new wave of fighting since December 2005, when a Norwegian-brokered truce began to unravel. The truce was formally ended by the government in January.
The military has pushed out the LTTE from its last bastion in the east of the tropical island, a victory that has largely confined the rebels to their area in the north.
The rebels have been battling for an independent homeland since 1972 in an ethnic conflict that has claimed tens of thousands of lives.