Bombs hit two Sri Lankan buses

(AP)

Two bomb attacks on buses in Sri Lanka killed at least 22 people today, security officials said, the latest in a series of assaults by suspected Tamil Tiger rebels on the country's transport system.

In the first attack, 20 people were killed and 64 wounded when a roadside bomb exploded during morning rush hour near a crowded bus in the capital Colombo, the military said.

Later on, an explosion hit a bus in the central town of Polgolla, killing at least two and wounding 20 others, police said.

The government blamed the Liberation Tigers of Tamil Eelam (LTTE) for the blast in Colombo, as well as other attacks on urban areas that have increased since the military began a new push against rebel territory in the north and east.

Today's blasts come two days after the military blamed rebels for a bomb attack on a railway track that wounded 27 civilians in Colombo.

The rebels, who are fighting for an independent state in the north and east, were not immediately available for comment but usually deny involvement in such attacks.

President Mahinda Rajapaksa called on people to remain calm.

"Remain vigilant against the forces of terror and continue to assist the police and security forces in the task of eradicating terrorism from our country," he said in an statement.

More than 70,000 people have been killed since civil war erupted in 1983.

A Reuters witness said the bus targeted in Colombo was shredded by shrapnel and the floor was covered in blood and debris.

"I was on my way to office and suddenly I heard a loud explosion and saw people screaming with blood all over," said Aruna Wickramarachchi, a 45-year-old hotel worker.

"My leg was also injured from the explosion," Wickramarachchi said, adding that she was among about 100 passengers on the bus.

An official with the police bomb disposal unit, who asked not to be identified, said the roadside bomb was detonated by remote control.