The leader of the Eelam People's Revolutionary Liberation Front -- Varatharajah Wing (EPRLF), Subathran (Eds: one name), 44, was killed at his office in Jaffna, officials said.

The party is bitterly opposed to the rebel Liberation Tigers of Tamil Eelam (LTTE), which entered into a truce with the government in February last year.

Until then, the LTTE Tamil Tigers had been fighting for a separate homeland on the northern Jaffna peninsula.

Despite the ceasefire, the Tigers have been accused of killing more than 30 rival Tamils and military informants.

Subathran is the most senior politician to have been killed during the truce.

His murder came as the navy engaged a suspected Tamil rebel vessel off the island's north-eastern coast. Details were not immediately available.

WAR.WIRE