At least six people have been killed and 75 wounded in a Tamil Tiger suicide attack against a bus carrying policemen in Sri Lanka's capital Colombo.

"Initial details have indicated that a motorbike ridden by an LTTE [Liberation Tigers of Tamil Eelam] suicide bomber rammed into the bus carrying policemen," military spokesman Brigadier Udaya Nanayakkara told AFP.

The bombing occurred outside a Buddhist temple in the Fort area of Colombo's commercial district.

The area is home to the official residence of the island's president, the five-star Hilton Hotel and the twin-tower World Trade Centre office complex.

The attack comes amid a mounting government offensive against the LTTE's mini-state in the north of the island.

The government pulled out of a Norwegian-brokered truce in January, and claims to have inflicted massive casualties on the rebels so far this year.

The LTTE are fighting for a separate Tamil homeland in the north and east of the ethnic Sinhalese-majority island.

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