Heavy fighting across Sri Lanka's north left at least 35 Tamil Tiger rebels dead, the defence ministry said on Monday.
Nine government soldiers also died on Sunday, including three in an accidental hand grenade explosion in Jaffna, the statement said.
There was no comment from the Tamil Tigers.
The latest fighting raises the number of rebels who have died in combat since January to 5,531, while 505 soldiers have been killed in the same period, according to a tally of defence ministry claims.
Independent verification of government figures is not possible as Colombo bars reporters from travelling to the combat zones.
Tens of thousands have died since the Liberation Tigers of Tamil Eelam launched an armed struggle in 1972 aimed at carving out a separate homeland for minority Tamils in the island's north and east.