Colombo, Feb.3: The Sri Lankan Army on Sunday claimed to have killed 27 Tamil rebels in fresh clashes.

According to sources in the country's  defence ministry, the clashes took place in the Northern Districts including Manar.

Meanwhile in another incident of violence,a grenade exploded at a zoo on the outskirts of Sri Lanka's capital, wounding four people.

Military sources were quoted as saying that the explosion took place in Dehiwela, a suburb of the capital Colombo.

Sunday's explosion occurred a day after a bomb blast on a bus killed 18 people and wounded 51 others in Central Sri Lanka.

So far, over 700 people have been killed in intensified violence since the government withdrew from a cease-fire with the Tamil Tigers.

The Tigers have been fighting for an independent state in the north and east of Sri Lanka since 1983.

The attacks come amid increased security ahead of celebrations on Monday to mark the 60th anniversary of Sri Lanka's independence from Britain.(ANI)