But Seevanatnam Puleedevan, a Tiger spokesman, said 66 soldiers and 12 rebels had died in the clashes.
The Sri Lankan army and Tamil Tiger rebels have exchanged artillery fire across their frontlines in Muhamalai, on the Jaffna peninsula, since Thursday, the government official said on Tuesday.
The government says that 35 soldiers and 150 rebels have been killed during the battle.
Both sides are known to exaggerate each other's death tolls and journalists and other independent observers have not been allowed to enter the Muhamalai area.
Soldiers have advanced up to 1km into rebel territory in Jaffna and captured a forward bunker line used by the rebels to fire mortars at government troops, official said in recent days.
But Puleedevan denied that the Tigers' bunkers had been overrun and said they continued to resist government troops.
Also on Tuesday, a roadside bomb exploded near the northeastern port town of Trincomalee, injuring three policemen, senior police official Nihal Samarakoon said.
Jaffna has long been a flash-point for violence in Sri Lanka's 19-year war between the Sinhalese-dominated state and Liberation Tigers of Tamil Eelam, who claim it as the cultural heart of the country's 3.2 million ethnic Tamil minority.
Although a 2002 ceasefire agreement temporarily halted large-scale hostilities, weeks of escalating battles along borders separating rebel and government-held territory in the northeast have left it in tatters.