Sri Lankan air force jets bombed two Tamil Tiger bases in the country's northwest yesterday, the military said.
"Two bases of the Sea Tigers were bombed today," military spokesman, Brigadier Prasad Samarasinghe said.
The Sea Tigers are the naval wing of the separatist Tamil Tiger rebels, who say they are fighting to create a separate homeland for the country's 3.2 million ethnic Tamil minority.
"We have destroyed both the bases," Samarasinghe said, adding that he had no details on casualties.
The attack came one day after a roadside bomb exploded in Sri Lanka's northern Jaffna peninsula, killing one soldier and wounding three others, the military said, blaming Tamil Tiger insurgents for the blast.
"We suffered casualties, but our troops did not fire back as there was a presence of civilians in the area,'' Samarasinghe said.
The incident late on Tuesday was the latest in a spike in violence that has pushed the tropical island closer to all-out war.
The military, also late on Tuesday, found a similar explosive near the town of Ampara, in eastern Sri Lanka, Samarasinghe said.
He said the army's bomb disposal unit was called in to defuse the lethal device that fires hundreds of steel balls and can be triggered by remote control.
This particular type of explosive is a favorite weapon of separatist Tamil Tigers in their fight against security forces.
There was no immediate comment from the rebels on the explosions, but the group later accused the military of trying to destroy a bridge connecting a rebel-held village in the east with the rest of the island.
"This bridge is an essential part of the A-15 highway [leading] to Vaharai, the only highway to the 36,000 besieged people in Vaharai," the rebels said in an e-mail.
"It is therefore a humanitarian link that is now being attacked by the Sri Lankan military with the intention of destroying it," the rebels said, adding that the shelling had started yesterday morning.
Some 36,000 people, mostly ethnic Tamils, have been trapped in the village since fighting intensified last month.
Aid agencies have said that civilians are increasingly being caught up in Sri Lanka's escalating conflict and have warned that access to them has become very limited.
The military was not immediately available for comment, as top officials were in a meeting, officials said.
Since last December, airstrikes, mine attacks, assassinations and regular exchanges of heavy arms fire have killed more than 3,200 fighters and civilians in the troubled country.
Both sides insist they have not withdrawn from a 2002 truce brokered by Norway that halted two-decades of civil war.
With peace talks stalled, the government and the rebels refuse to budge from their positions.