COLOMBO, July 28 (Reuters) - Sri Lanka's navy said it sank two Tamil Tiger vessels off the island's northwest coast on Saturday, killing six insurgents in the latest clash in a renewed civil war. The Navy said the rebel boats were hidden among a fleet of fishing boats from neighbouring India in waters off Mannar, close to the rebels' de facto state in the far north. "We detected a cluster of 60 Indian fishing boats and when we went closer, two of the boats started to go faster and fired rocket-propelled grenades and fired small arms," said navy spokesman Commander D.K.P. Dassanayake. "The navy retaliated and sank the two boats. There were four people in one and two in the other." The Liberation Tigers of Tamil Eelam were not immediately available for comment, and there was no independent account of what happened. A suspected rebel roadside bomb on July 24 killed 12 soldiers aboard an army bus in the restive north. An estimated 4,500 people have been killed since last year in attacks, battles, air raids and ambushes. Earlier on Saturday, the military said they found two rebel suicide bomber jackets in the army-held Jaffna peninsula in the far north, which is cut off from the rest of the island behind Tiger lines. Evicted from swathes of the east by military offensives in recent months, the Tigers have vowed to switch to guerrilla tactics against economic and military targets in a bid to cripple the island's $23 billion economy. They say peace is impossible with President Mahinda Rajapaksa, who is determined to take control of all rebel-held territory and flatly rejects their demands for an independent state. Analysts say that sets the stage for a bloody fight for the north where the conflict is now concentrated. Nearly 70,000 people have been killed since 1983, and analysts see no clear winner on the horizon.
