(Updates bombing death toll, adds air raids, fighting)
COLOMBO, Dec 28 (Reuters) - A suspected Tamil Tiger suicide bomber killed eight people including six paramilitary guards in Sri Lanka's capital Colombo on Sunday while air force jets bombed rebel positions in the far north.
Military spokesman Brigadier Udaya Nanayakkara said the Tamil Tiger rebel targeted a security checkpoint near a crowded market in the northern suburb of Wattala.
"The death toll has gone up to eight people including six civil defence force personnel, one army officer and a civilian," Nanayakkara said. He said 17 others were injured and being treated at two hospitals.
A Reuters witness said the site of the blast had been cordoned off.
While Sri Lanka's military blamed the rebels for the blast, the Liberation Tigers of Tamil Eelam (LTTE) did not immediately comment on the attack and has in the past denied responsibility for such attacks.
Military officials said air force fighter jets had bombed rebel positions in the far north of the country, hours after the suicide attack.
Earlier, the Sri Lankan navy said it had killed four rebels and destroyed a rebel boat in the north.
The military said heavy fighting continued around the rebels' self-proclaimed capital Kilinochchi in the northern war zone.
Sri Lanka's military has been closing in on Kilinochchi since September and in the past two weeks has been assaulting heavy defences encircling the town's outskirts.
The LTTE had no immediate comment on the fighting but pro-rebel website www.tamilnet.com quoted unnamed Tamil Tiger rebel officials saying at least 50 Sri Lankan army soldiers were killed and 90 wounded in the northern district of Mullaitivu in fighting on Saturday.
It said LTTE officials recovered 16 dead bodies of army soldiers in the clearing mission that followed.
The military admitted the fighting took place but said the rebels had overblown the figures.
It is nearly impossible to verify battlefield claims since both the government and the LTTE block independent media access to the war zone, and have repeatedly distorted figures to their advantage.
The LTTE started fighting the government in 1983. It says it is battling for the rights of minority Tamils in the face of mistreatment by successive governments led by the Sinhalese majority since Sri Lanka won independence from Britain in 1948. (Additional reporting by Shihar Aneez; Editing by Valerie Lee)
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