By Roland Buerk
BBC News, Colombo
Sri Lanka's navy has fought a battle with a flotilla of Tamil Tiger boats off the island's north-east coast.
The Sea Tigers are said to be based in the north of Sri Lanka
It comes days after officials said a navy fast-attack craft was sunk by a sea mine. The rebels claimed it was sunk by a suicide attack.
Meanwhile, fighting is continuing on land too.
Battles have intensified since January when the government pulled out of a ceasefire. It has vowed to crush the rebels by force.
The latest sea confrontation took place in the middle of the night.
A navy patrol spotted a small flotilla of Tamil Tiger boats hugging the coast and opened fire.
Navy spokesman Lt Cdr Rohan Joseph said one rebel vessel was disabled in the fighting but he had no details on whether anyone on board was wounded or killed.
On Saturday a navy fast-attack craft was sunk in the same area.
Ten sailors are missing and now presumed dead.
The navy said the vessel most likely hit a sea mine planted by the tigers, but the rebels say it was destroyed in a suicide attack by the so-called Black Sea Tigers.
On land the fighting is continuing too, despite rains and flooding.
The military claims more than 500 rebel fighters have been killed in the last three weeks, 10 times as many casualties as the security forces have suffered.
Both sides are accused of exaggerating the loses they inflict while playing down their own to maintain morale on the front lines.