A bomb ripped through part of a packed passenger train during evening rush hour Monday, killing eight people and wounding 70 others near the Sri Lankan capital.

Military spokesman Brig. Udaya Nanayakkara blamed Tamil Tiger rebels for the bombing near the railroad station in Dehiwala, about six miles south of Colombo.

Rebel spokesman Rasiah Ilanthirayan did not respond to calls seeking comment but the rebels routinely deny such attacks.

Television footage showed the blast ripped off part of the train compartment's roof and windows were shattered. Bloodstained bags, umbrellas, glasses and other debris were strewn throughout the compartment.

Dr. Wifred Kumarasiri said six bodies were brought to Kalubowila Teaching Hospital and two people later died there. Another 70 were being treated, he said.

• Click here to see photos of the blast.

The rebels, blamed for scores of suicide bombings and other attacks on civilians, are listed as a terrorist group by the United States, the European Union and India.

If the attack was carried out by the rebels, it would show they retain the ability to strike deep inside government territory despite a maze of security checkpoints around the capital and suburbs.

Monday's bombing was the second attack in four days targeting civilians. A bomb last Friday in the rebel stronghold of Kilinochchi killed 16 people. Tamil Tigers blamed that blast on government forces — a charge the government denies.

Authorities, in the past weeks, have asked the public to remain vigilant. On Saturday evening, police defused two time bombs hidden on passenger buses during rush hour near Colombo.

A blast that was blamed on rebels killed 26 people last month at a Colombo bus station.

Nanayakkara said the rebels "are trying their level best to create problems in Colombo and suburbs" because of defeats they suffer at the hands of government troops.

"They (rebels) are desperate in the northern fronts and now attack civilians elsewhere," he said.

The Tamil Tigers have fought since 1983 to create an independent homeland for ethnic minority Tamils, who have been marginalized by successive governments controlled by the majority Sinhalese. More than 70,000 people have been killed.

Fighting has escalated along the northern front lines since the government withdrew from a long-ignored cease-fire in January.

The government has pledged to capture the rebels' de facto state in the north and crush them by the end of the year. But diplomats and other observers say the army is facing more resistance than expected.

In the latest fighting, air force helicopters Monday bombed a Tamil rebel position in the north, a day after ground clashes around the rebel stronghold killed 21 insurgents and a soldier, according to the military.

A military statement said that the air force targeted a rebel point in Andankulam village of northern Mannar district to back up the infantry operations. It did not identify the rebel location nor release details of damages.

Ground fighting on Sunday were reported from Jaffna, Vavuniya, Mannar and Welioya regions, the military said.

There was no immediate comment from rebels on military's claims. It was not possible to get independent accounts of the violence because reporters are not allowed in the war zone.

Both sides are known to exaggerate casualties inflicted upon their enemy while lowering their own damages.