A soldier on guard in Colombo on Friday. (AP)

Colombo, Nov. 10 (Agencies): A prominent Tamil politician was assassinated in the Sri Lankan capital today and a naval attack on two Tamil Tiger boats left six rebels dead as the South Asian country was drawn closer to full-scale war.

Nadaraja Raviraj, a member of the Tamil National Alliance (TNA), was leaving his house in Colombo when he was approached and shot at close range, said K. Sivajilingam, a fellow MP. Raviraj’s bodyguard was also killed.

President Mahinda Rajapakse condemned the killing, calling it a “cowardly act” by “those opposed to dissent and political pluralism in a democratic society.”

But the Tamil party blamed the government for the killing. “We understand that a whole magazine has been emptied on them in broad daylight,” TNA lawmaker Suresh Premachandran said. “This is a clear message to Tamil parliamentarians: ‘Don’t open your mouth.’”

Government spokesman Keheliya Rambukwella said it was unfair to blame the government before an investigation could take place, adding that the President had asked for help from London’s Scotland Yard in the investigations of a series of events — including Raviraj’s killing — to determine whether Tamil rebels were orchestrating crimes to blame the government.

US assistant secretary of state Richard Boucher, who is visiting India, said both Washington and New Delhi were “very concerned” about the situation in Sri Lanka. “That’s another horrible act, it’s really deplorable,” he said. Military officials said the navy had spotted two rebel suicide boats hidden among fishing boats in seas off the eastern district of Trincomalee and opened fire.

That clash came after the military said it had destroyed 22 rebel vessels off the island’s northern tip late yesterday. “We detected two suicide boats (off Trincomalee) this morning and fired at them. There was a huge explosion and they were completely destroyed,” a military spokesman said.