A sea battle launched by Tamil Tiger rebels Thursday in northern Sri Lanka left about 50 insurgents and 17 government sailors dead or missing, the navy said.
The government and a team of European-led monitors accused the Tigers of violating a 2002 cease-fire accord with the attack, which sank a navy patrol boat off the northern coast. Government troops retaliated, sinking five rebel boats and launching airstrikes on guerrilla-held territory, putting the worst strain yet on the truce that halted two decades of warfare.
The Tigers, formally known as the Liberation Tigers of Tamil Eelam, launched their attack in 15 small boats against a navy convoy escorting a troop carrier with 710 soldiers aboard, navy spokesman Cmdr. D.K.P. Dassanayake said.
"Navy fast-attack boats escorting the vessel engaged the Tiger boats, and one of them was destroyed by a suicide boat," he said.
Fifteen sailors and two officers were on the downed navy boat. At least 50 guerrillas were on the rebel boats that sank, and all were believed dead, Dassanayake said.
A pro-rebel website quoted unnamed rebel sources as saying they had lost only four guerrillas. No verification of the casualty toll was immediately possible.
Helen Olafsdottir, spokeswoman for the European-led Sri Lanka Monitoring Mission, said a truce monitor was in the troop carrier with the soldiers.
"This is very serious," she told BBC television.
More than 150 people have died in escalating violence since the beginning of April, reports Los Angeles Times.