Seven people were killed and 26 wounded when suspected Liberation Tigers of Tamil Eelam rebels blew up a civilian bus in northern Sri Lanka on Saturday.

The bomb, planted on a tree-top, exploded as the crowded bus passed by in the Vavuniya district, 250 km north of Colombo, a police official in the area said over telephone.

Among those dead was a soldier, hospital sources in Vavuniya said, adding that seven soldiers escaped with injuries.

There was no immediate word from the Tamil Tiger rebels.

The attack came five days after a bomb exploded inside a bus in the east of the island, killing 17 people and wounding 25.