Five Sri Lankan sailors have died in a clash with Tamil Tiger rebels off the country's west coast, the navy says.
Navy spokesman DKP Dassanayake said about 20 rebel small craft had attacked two naval vessels near Kalpitiya, about 140km (86 miles) north-west of Colombo.
He said 12 rebels had also been killed. The Tamil Tigers say only one rebel died. A rebel spokesman blamed the navy for provoking the clash.
Worsening violence has claimed about 700 lives in Sri Lanka this year.
Commander Dassanayake said the rebels attacked near a small naval base by a lagoon in Kalpitiya.
"As they approached, our craft went and engaged with them," he told Reuters news agency.
"One of our craft got damaged... Two of their boats were destroyed."
Air support was then called in, he said, and the rebels repulsed.
The bodies of the five sailors were recovered from the sea near the damaged boat, the military says.
The rebels say they sank one of the navy vessels.
"Our boats were moving in that area when the Sri Lankan navy interrupted them and opened fire," rebel spokesman Daya Master told Reuters news agency.
In a separate incident, one soldier was killed and at least three other people injured when rebels attacked an army camp with mortar fire in the eastern district of Trincomalee, an army spokesman said.
Wednesday's incident came as the military prepared for the funeral of a top army general killed on Monday.
Maj Gen Parami Kulatunga died when a suicide bomber on a motorcycle crashed into his car, the military says. A spokesman for the Tigers denied involvement in the attack.
The rebels and the government say they still stand by a truce deal - but with rising unrest, the peace exists only on paper, the BBC's Dumeetha Luthra says.
Many victims of the violence have been civilians and members of the security forces.
Many Tamil civilians have also been killed over that time - by the security forces or affiliated paramilitary units, the rebels allege. Others blame some of those deaths on the rebels or other armed groups.
More than 60,000 people have died in Sri Lanka since the rebels began their fight for independence for minority Tamils in the 1970s.