(Updates with revised death toll, and analyst comments)

By Ranga Sirilal

COLOMBO, Feb 2 (Reuters) - A bomb exploded on a civilian bus in the central Sri Lankan town of Dambulla on Saturday, killing at least 18 people and wounding 50, the military said.

The explosion was the latest in a series of bomb attacks blamed on the Liberation Tigers of Tamil Eelan (LTTE), the rebel group fighting to create an independent state in the island's north and east.

"There were 18 people killed and not 20 as earlier," said military spokesman Brigadier Udaya Nanayakkara. He said 50 others were injured in the blast, but hospital authorities counted dozens more.

"The explosion is a work of the LTTE."

The military said the victims were travelling north from the central town of Kandy to Anuradhapura to attend a religious ceremony.

Hospital authorities said many of those hurt had had serious head injuries or suffered burns.

"We have got about 93 injured," said Dr. Sudarshana Arambegedera, director of Dambulla Hospital, adding 16 of the fatalities were women.

Dambulla is around 150 km (90 miles) north of the capital Colombo.

Local television showed footage of the aftermath of the explosion. The bus's roof was partly blown off, windows were shattered and the vehicle's steel frame bent and torn.

Many of the injured were taken to hospital by civilian vehicle.

The attack came as Sri Lanka was preparing to celebrate on Monday its 60th year of independence from Britain, and the military had stepped up security over concerns of attacks.

The Military also said they found two suicide jackets and some other war materials near a fish stall in a suburb of the capital, Colombo, hours after the blast.

Saturday's blast occurred at a bus station and came about three weeks after a roadside bomb ripped through a civilian bus killing 27 people and wounding dozens in the central town of Buttala.

Analysts see an escalation of violence against civilians with the government and the Tamil Tiger rebels locked in a new chapter of 25-year old civil war after a six-year ceasefire between the state and rebels expired on Jan. 16.

"If we continue try to solve this problem with violence, we will kill more of the people we are trying to protect and save," said Paikiasothy Saravanamuttu of the Centre for Policy Alternatives.

The Tigers were not immediately available for comment.

The majority-Sinhalese government has vowed to wipe out the Tigers militarily. Earlier this month it scrapped the ceasefire, saying the Tigers had used it to regroup and rearm.

Nordic truce monitors, asked to leave Sri Lanka by the government, say both sides repeatedly violated the ceasefire.

Clashes between the rebels and government troops have escalated since the truce was scrapped last month. The two-decade conflict has killed an estimated 70,000 people. (Editing by David Fox)

AlertNet news is provided by