Colombo  - A suicide bomber killed at least eight people, including six paramilitary guards, and injured 17 on the outskirts of Colombo Sunday, military spokesman Udaya Nanayakkara said.

The suspected Tamil rebel detonated himself at a paramilitary guard post located in Wattala, 10 kilometres north of the capital.

An army captain and a civilian were among those killed, while at least 10 of the victims had been in the area to attend a Sunday fair.

The incident came hours after the Sri Lanka navy destroyed a Tamil rebel boat and killed at least four rebels off the northern coast, a navy spokesman said.

The naval attack took place off Point Pedro, more than 400 kilometres north of the capital, shortly after midnight Saturday.

Government troops have intensified military operations against the Tamil insurgents in the north. (dpa)