Bombs mar Sri Lanka independence day

COLOMBO, Sri Lanka (CNN) -- A series of explosions tore through Sri Lanka Monday as the country celebrated its independence day.

The government immediately blamed the Tamil Tiger rebels for the attacks, which killed 12 civilians and one soldier in separate incidents.

A roadside bomb ripped through a bus in northeast Sri Lanka Monday, killing 12 passengers and injuring 17 others, the military told CNN.

The bus was carrying passengers from one village to another in the Welioya region when it was struck.

A few hours earlier, another bomb hit a military tractor in Buttala in the southern part of the country, military officials said. One soldier died in the explosion; three others were injured.

The military said the tractor was pulling a trailer containing lunch for soldiers.

The blasts come amid heightened security in the capital city Colombo and elsewhere for the country's independence day celebrations. Sri Lanka on Monday celebrated its 60th year of independence from British rule.

At a tightly guarded ceremony, Sri Lankan President Mahinda Rajapakse said his forces were winning the battle against the Tamil Tigers, and expressed confidence that the government would emerge victorious.

The two roadside bombs occurred shortly after the speech.

Earlier in the day, two other explosions rocked the outlying areas of Colombo, but did not claim any casualties.

One destroyed a power transformer, and several houses in the area. The other went off in an open field, authorities said.

The island nation in southeast Asia is already in chaos as government and rebels continue a battle that is taking an increasingly deadly civilian toll.

A female suicide bomber detonated a bomb Sunday as a train pulled into a Colombo railway station, killing at least 12 people -- most of them students -- and wounding more than 100 others.

On Saturday, a bomb explosion on a bus in a tourist town north of Colombo killed 20 people and sent at least 68 others to the hospital, authorities said.

Sri Lanka has been in turmoil since Jan. 16, when the government withdrew from a cease-fire with separatist rebels known as the Tamil Tigers.

The fighting in Sri Lanka pits government forces in a country dominated by the Sinhalese ethnic group against rebels from the Tamil minority. The rebels are fighting for the creation of an independent nation, citing discrimination by the Sinhalese. E-mail to a friend

Journalist Amal Jayasinghe contributed to this report.

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