COLOMBO, July 5: At least three people were killed in fresh violence in Sri Lanka on Thursday as the Tamil Tigers commemorated 322 suicide bombers who have blown themselves up in the past 20 years, officials said.

Suspected rebels triggered a roadside blast in the northern district of Vavuniya, killing a civilian, military officials said with two soldiers killed in a separate clash in the same region.

There was no immediate word from the Tigers about the latest clashes which came as security forces set up snap roadblocks and checkpoints in the capital, Colombo, and prevented heavy vehicles from passing key government buildings.

The measures were taken following fears that the rebels could try to mark “Black Tiger” day with a bombing, officials said.

“Measures are under way to heighten our alert during the Black Tiger week,”said Senior Deputy Inspector General Jayantha Wickramaratne, a police spokesman.

“We are taking all measures to eliminate the risk of terrorist attacks,” he said.

The Liberation Tigers of Tamil Eelam (LTTE), who have been fighting for a separate homeland since 1972, have frequently staged their trademark suicide attacks around religious services for the fallen “martyrs.” The group's first suicide attack was by a guerilla known as Captain Miller, who drove a truck bomb into an army camp on the Jaffna peninsula on July 5, 1987, killing 40 government soldiers.

The pro-rebel Puthinam.com website said 322 members of the elite Black Tiger suicide units had perished in attacks and that the group had deployed 61 suicide bombers in the past year alone.

Puthinam.com said 241 of the suicide bombers were killed in sea-going attacks while the others had died in ground operations.

The guerillas held Hindu religious services in rebel-held territory Thursday to invoke blessings for the Black Tigers, regarded by rebel chief Velupillai Prabhakaran as the group's protective armour.

In March, the Tigers staged their first air attack using light aircraft, and the new Tiger air wing has fuelled fears they could use a “flying bomb.” The guerrillas have flown at least four bombing sorties against troops and economic targets in Sri Lanka, covering more than 250 kilometres back to rebel-held territory despite a barrage of ground fire.The deadliest Black Tiger attack happened last October when rebels drove a truck bomb into a transit point where 350 sailors were waiting to board buses, killing at least 116 of them.

Since then, tighter security has been in place when troops move in large groups.

The latest Black Tiger anniversary comes amid an upsurge of fighting in Sri Lanka. More than 5,000 people have been killed in the new wave of bloodshed since December 2005.

The Tigers are fighting for an independent homeland for the minority ethnic Tamils on the majority Sinhalese island. The 35-year-old conflict has claimed more than 60,000 lives.—AFP