A bomb explosion at an army checkpoint killed on Monday six people and wounded 14 in the island nation's northeast, and an anti-personnel mine blast in the east wounded two commandos on route-clearing duty, the army said.

The bomb was hidden in an auto-rickshaw that blew up when security forces went to check it, said army Brigadier Prasad Samarasinghe.

Those killed were four police, one soldier and one civilian, he said.

Twelve civilians who were riding past the checkpoint in a bus when the explosion occurred were wounded, Samarasinghe said. Nine of them were in critical condition.

Two soldiers stationed at the checkpoint at the entry to the port city of Trincomalee, 215km (135 miles) northeast of Colombo, were also wounded, he said.

Blaming the Tigers

No one claimed responsibility for the blast. Samarasinghe blamed it on the country's Tamil Tiger rebels.

Also on Monday, a mine suspected to have been triggered by rebels in the northern Jaffna Peninsula killed one soldier and wounded another, the army spokesman said. The two were on foot patrol in Nelliady, a small town nearly 300km (200 miles) north of Colombo.

Suspected rebels also fired at the soldiers in the Vavuniya sector early on Monday. The army returned fire, killing an attacker wearing a Sri Lankan army uniform, an army statement said.

Another mine was triggered while commandos were checking a road for mines in the eastern district of Batticaloa before military vehicles were scheduled to pass, Samarasinghe said.

The mines are a weapon favoured by rebels, who have been fighting since 1983 for a separate homeland for minority ethnic Tamils. More than 65,000 people have died in the conflict.

A 2002 cease-fire halted the fighting. But peace talks broke down, and recent escalating violence has killed more than 700 people since April, threatening a return to full-scale war.