Military spokesman Brig. Prasad Samarasinghe said air force jets took out rebel positions overnight in Sampur, where rebels have been firing artillery and mortar shells at a port the military uses to send supplies to its 43,000 troops in the northern Jaffna Peninsula.
The military's push to recapture the 19-square-mile area, across a lagoon from the strategic Trincomalee naval base, has opened a new front in the country's conflict with the ethnic Tamil insurgents.
Sri Lanka's top military official, Lt. Gen. Sarath Fonseka, told The Associated Press on Thursday that government troops would take the area within a few days.
S. Elilan, a regional leader of the Liberation Tigers of Tamil Eelam, said: "This is an area under our control and Tamil people live here. We will not allow the military to invade."
The Tigers want to establish a homeland for the country's Tamil minority in the north and east, claiming discrimination by the Sinhalese majority.
The military claims to have killed 101 Tigers and wounded 100 more since late Sunday, the start of the Sampur operation. Only 14 soldiers have been killed, it says.
The rebels have reported 82 deaths — 50 government soldiers, 12 rebel fighters and 20 civilians.
Also Friday, Tigers were suspected of having triggered a roadside bomb in northern Jaffna, killing one soldier and injuring five, Samarasinghe said. In a nearby village, unidentified gunmen killed two Tamil civilians on a motorbike, the military said.
Roadside bombings and shootings are frequent in Tamil-majority Jaffna, under government control since 1995 but still considered the heart of Tamil culture.
The rebels made a major push to reclaim the peninsula on Aug. 11. A resulting 11-day battle killed at least 1,000 combatants and civilians.
The peninsula has since been virtually isolated, with road, sea and air access cut off.
Airlines said Friday they were preparing to resume commercial flights from the capital to the peninsula, but were still waiting for security clearance from the military.
In recent months, Sri Lanka has returned to the brink of full-scale civil war with hundreds of fighters and civilians killed in major offensives. However, neither side has officially withdrawn from the 2002 Norway-brokered cease-fire.
About 220,000 people have been made homeless by near-daily shelling, airstrikes and artillery fire since April, according to the United Nations.
The Tigers have fought the government since 1983. The conflict killed more than 65,000 people before the cease-fire.