Blasts kill 5 in Sri Lanka as police probe bus bombing

COLOMBO, Jan 6 (Reuters) Suspected Tamil Tiger bomb attacks killed four soldiers and a civilian in north Sri Lanka today, as police questioned 18 people over a blast that killed six civilians and injured dozens on a bus a day earlier.

Three soldiers and a civilian were killed when a truck was ambushed with a Claymore fragmentation mine in the northern district of Vavuniya, while another soldier was killed in a pair of similar attacks in the northern Jaffna peninsula.

Police were still scouring for the culprits of yesterday's bus bombing 36 km outside Colombo -- the second such attack to directly target civilians rather than the military or politicians -- but had not yet made any arrests.

Officials put the bus blast death toll at six, including one child, and said around 60 other passengers were injured, 10 of them seriously.

''We are still investigating. At the moment 18 people are being questioned, but no one is in custody,'' said E W Prathapasinghe, a Deputy Inspector General of Police for the island's Western Province.

The military said it fought artillery duels early on Saturday with the Tigers in the restive eastern districts of Trincomalee and Batticaloa, from where it has vowed to drive the rebels out in violation of the terms of a now tattered 2002 truce.

However there had been no new air raids after four straight days of aerial bombings of suspected Tiger bases in the north and east.

Analysts say the attack on the civilian bus raises the spectre of a return to a past Liberation Tigers of Tamil Eelam (LTTE) tactic of attacking civilians. The rebels have focused on military and political targets so far during a new chapter of the island's two-decade civil war in recent months.

The Tigers were not immediately available for comment, but routinely deny involvement in bombings and ambushes.

''Yesterday's bombing bears all the hallmarks of Tiger attacks,'' said Iqbal Athas, an analyst for Jane's Defence Weekly.

''The fact that they have now started targeting (civilians) is a cause for concern.'' ''One cannot rule out more attacks on civilians,'' he added, saying he believed the blast was a tit-for-tat attack for civilians the rebels say have been killed in Tiger territory by troops or artillery shelling.

More than 3,000 troops, civilians and rebel fighters were killed in a spree of ambushes, suicide bombings, air raids, naval clashes and land battles last year despite the ceasefire, which international monitors say now exists only on paper.

Tens of thousands of ordinary civilians have been displaced yet again by renewed fighting are now living in rudimentary camps set up in schools, fields and even temples in goverment territory -- many of whom were still striving to rebuild their lives after the 2004 tsunami.

While the fighting has been largely confined to the north and east, many fear an all-out return to a war that has killed more than 67,000 people since 1983 could spread throughout Sri Lanka and be catastrophic for the 23 billion dollars economy.

The Tigers, who accuse successive Sinhalese-majority governments of discriminating against minority Tamils, have vowed to intensify their fight for an independent state in the north and east after President Mahinda Rajapakse rejected their demands for a separate homeland.

REUTERS SP RK1242