The Liberation Tigers of Tamil Eelam (LTTE) arranged Hindu religious services across the territory under their control to mark Wednesday's 19th anniversary of their first suicide bombing.

"Security is already tight, but we take note of such anniversaries because there could be an escalation (of violence) at this time," a senior police officer said Tuesday, a day after eight people were killed and dozens wounded in three mine blasts in the north.

An upsurge of bloodletting since December between the majority Sinhalese and minority Tamil population has killed more than 830 people and strained a shaky truce brokered by Norway in 2002.

"There's a bigger security deployment on the ground," the officer said.

The pro-rebel Nitharsana-m.com website said the Tigers will pay homage to the bombers from their suicide squad on Wednesday.

"Events to observe the Black Tigers' day at government and public institutions in the (rebel-held) Wanni (area) have also been organised," the website said.

A man known as Captain Miller drove a truck packed with explosives into an army camp in the Jaffna peninsula 19 years ago, killing 40 soldiers and starting the cult of suicide bombings, which emerged a trademark of the Tigers.

Two days after the 2004 Black Tiger anniversary, a woman suicide bomber blew herself up and killed four policemen who were about to search her at a Colombo police station.

For LTTE chief Velupillai Prabhakaran, 51, the suicide bombers are the "protective armour" of his separatist movement which started in 1972 as a rag-tag band but is now regarded as a ruthlessly efficient killing machine.

The Tigers have been blamed for a number of high-profile victims, including former Indian premier Rajiv Gandhi and Sri Lankan President Ranasinghe Premadasa.

A former US deputy secretary of State, Richard Armitage, described the LTTE as an outfit "best known for pioneering the practice of turning its sons and daughters into human bombs."