(Recasts with civilian bus blast)

By Simon Gardner

COLOMBO, Feb 4 (Reuters) - Suspected Tamil Tiger rebels killed 13 people with two roadside bombs on Monday, just hours after the government celebrated the island's 60th anniversary of independence with a parade of military might in the capital.

At least a dozen people were killed and 17 hospitalised in a suspected rebel bombing of a civilian bus in the north-eastern town of Weli-Oya.

A soldier also died and three others wounded when their army tractor was blown up by a bomb near the southeastern town of Buttala, officials said.

They were the latest in a series of deadly attacks as a 25-year civil war between the state and separatist Liberation Tigers of Tamil Eelam escalates.

"It was a Tamil Tiger Claymore mine targeting a civilian bus in Weli-Oya," a military spokesman said of the attack in the north-eastern district of Polonnaruwa, about 200 km (120 miles) from Colombo.

Thousands of police and troops were on high alert in the capital Colombo earlier on Monday as a defiant Sri Lankan military paraded tanks and troops as fighter jets flew overhead amid fears Tiger rebels would attack the celebrations.

The parade came a day after a suspected female Tiger suicide bomber killed 11 people and wounded 92 in an attack on the island's main train station, which sits a few hundred metres from the site of Monday's parade.

On Saturday, a bomb exploded on a civilian bus in the central town of Dambulla, killing at least 18 people and wounding 50, the military said.

The military have captured vast swathes of territory from the Tigers in the east of the island, and are now pushing to evict them from their northern stronghold, though analysts say the rebels continue to prove they retain their strike capability.

"Two years ago no-one believed that terrorists could be defeated but during the last two years we made it a reality in our motherland," President Mahinda Rajapaksa said in an address to assembled military top brass, politicians and diplomats, referring to territorial gains in the east.

"We have had the cancer of terrorism for three of the six decades since independence," he added. "The challenge bestowed on us by history is the defeat of terrorism and the development of the country."

Troops and brass bands marched by after he spoke, accompanied by multi-barrel rocket launchers, armoured personnel carriers and artillery pieces. Navy fast-attack boats cruised past and attack helicopters and jets flew overhead to mark independence from colonial ruler Britain.

SCHOOLS CLOSED IN FEAR

Sri Lanka's education ministry, which shut 12 schools ahead of Independence Day because of security operations, said about 40 state schools in Colombo district would remain shut this week because of fears of violence.

Military spokesman Brigadier Udaya Nanayakkara said the armed forces had expected the rebels to try to mount attacks to disrupt the celebration, which comes just weeks after Rajapaksa withdrew from a 6-year-long ceasefire pact with the rebels.

Fighting between the Sri Lankan military and the LTTE rebels has intensified since the government scrapped the truce last month to the horror of the international community, saying the rebels were using it to rebuild and re-arm and were not sincere about talking peace.

Hundreds of people have been reported killed in recent weeks and analysts say both sides tend to exaggerate enemy losses. An estimated 70,000 people have died since the conflict began in 1983. (Additional reporting by Ranga Sirilal; Editing by David Fogarty) (simon.gardner@reuters.com; +94-777-686-030; Reuters Messaging; simon.gardner.reuters.com@reuters.net))

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