At least 90 people, most of them sailors, were killed on Monday in a suicide bombing by suspected Tamil rebels on a convoy of buses in north-central Sri Lanka [Images], military officials said.

Brigadier Prasad Samarasinghe, a military spokesman, said a suicide bomber rammed a truck filled with explosives into the naval convoy that was carrying sailors to the north-eastern port city of Trincomalee after they had finished their leave.

He said 68 sailors were confirmed killed and civilians working for the navy were also among the dead in the attack at Digampathana, between Dambulla and Habarana, 180 km north-east of Colombo.

"They were unarmed at the time of the attack," he said. "They only had a security escort with them."

The death toll could rise, Samarasinghe said, because some of the buses caught in the blast were still on fire.

At least 100 sailors were injured and brought to a hospital in Dambulla. Some were airlifted to Colombo.

At least 200 sailors were in the 15-bus convoy at the time of the blast, which damaged 13 of the vehicles.

The suicide attack was the biggest such attack since the government and the rebels signed a ceasefire in February 2002 under a Norwegian-backed peace process. Both the government and the Liberation Tigers of Tamil Eelam continue to remain parties to the truce despite recent fighting that has killed 2,500 people since December.

Samarasinghe said that attackers selected a transit point where soldiers returning from leave replace those going on leave. The location is not in the strife-torn northern and eastern parts of the country, where the LTTE has been fighting for a Tamil state for three decades.

The suicide bombing came amid fresh diplomatic efforts to persuade the LTTE and government to resume peace talks this month in Geneva and end a conflict that has killed 64,000 people.

Japanese peace envoy Yasushi Akashi arrived on Sunday and is to be followed by Norwegian peace envoy Jon Hanssen-Bauer as talks were scheduled on October 28-29.

The LTTE renewed their attacks on government forces in December, a month after President Mahinda Rajapakse was elected on a hardline campaign against the rebels. The fighting has been particularly intense since July.

The suicide bombing came a day after a vessel believed to be carrying arms for the Tamil rebels was destroyed off the north-western coast, killing at least six rebels.

The navy has intensified its deployments in the seas around Sri Lanka to prevent the LTTE from smuggling in military hardware.

Government forces last weeks suffered a major set back when 133 of their soldiers, including eight officers, were killed when they made an attempt to advance into rebel-controlled Muhamalai, 370 km north of Colombo.

-- DPA