COLOMBO, Sri Lanka (AP) _ Explosions rocked two buses in Sri Lanka on Tuesday night, killing at least one person and wounding 28 others, police said.

The first blast occurred at Watalla bus station, seven miles north of the capital, Colombo, killing one and injuring 15, police said. A short while later, another explosion wrecked a bus at Colombo's main bus station, wounding at least 13 people, police said.

People were boarding the second bus when the blast occurred, police said. The explosion blew off the roof of the bus, which then caught fire.

There was no immediate claim of responsibility. But police said they suspect Tamil Tiger rebels were involved.

The guerrillas have been fighting for a separate homeland for the minority Tamils in the island nation's north and east since 1983. They often carry out attacks in the Sri Lankan capital to attract attention to their cause.