COLOMBO, Sri Lanka (AP) _ The navy thwarted a suicide attack on a strategic port in eastern Sri Lanka at dawn Monday, killing eight Tamil rebels in the fighting but losing two of their men, a military spokesman said.

Almost simultaneously, an air force MI-24 helicopter was shot down six miles from Trincomalee, the port where the suicide attack took place, the air force said.

There were no immediate reports of casualties and it wasn't clear if the helicopter was coming to aid the navy in Trincomalee, which lies 149 miles northeast of the capital, Colombo .

In the suicide attack, navy guns opened fire on four rebel boats spotted approaching the port, Brig. Sanath Karunaratne said.

One boat packed with explosives rammed into a navy personnel carrier anchored at the port, damaging it when the bomb went off. The port itself was unharmed and remains safe, Karunaratne said. Three other rebel boats took direct hits from naval fire and exploded in the water.

He said there were at least two rebels in each of the four boats and all were killed. Before being hit by naval fire, rebels fired off mortars, killing two seamen.

The Liberation Tigers of Tamil Eelam have been fighting for 17 years to carve out a Tamil homeland out of Sri Lanka. Trincomalee falls within this desired homeland. The fighting has left more than 63,500 people dead.

Trincomalee is one of the finest natural harbors in South Asia. But it is rarely used for commercial trading because of the war.

Hours after the port attack, police found and set off a bomb in an abandoned bag in Colombo's business district.

The Sri Lankan capital is often targeted by Tamil suicide bombers who aim to kill political opponents or to cause economic hardship. On Thursday, a suicide bomber killed himself and two others in Colombia, after apparently failing to reach the government ministers who were the target.