PANICHACHANKANI, Sri Lanka -- Mainstream Tamil Tiger guerrillas advanced on a heavily armed breakaway faction yesterday in a vicious gun and mortar battle that killed at least nine people, wounded 20, and imperiled Sri Lanka's fragile two-year-old cease-fire.
It was the worst fighting since the 2002 truce halted the 19-year civil war. It occurred a week after voters rejected the government that had negotiated the cease-fire. The balloting elected a Parliament that backs the hard-line president.
Sri Lankan Army troops were told to stay out of the rebel conflict, but the fighting was occurring near army camps, where armed soldiers listened by radios to news of the factional guerrilla fighting along the Vergual River, 140 miles east of the capital, Colombo.
After hours of mortar and machine-gun fire, about 500 fighters from the breakaway group -- including women and teenage boys and girls -- withdrew from the area, saying they were repositioning rather than retreating.
"About 1,000 . . . people came and attacked us, so this is a tactical withdrawal and we are going to set up our new defense line," said S. Kumar, a senior commander of the breakaway group.
He said more fighters from the mainstream Liberation Tigers of Tamileelam were moving to fortify their freshly gained positions on the opposing side, indicating another offensive maneuver was likely.
Members of the main 9,000-strong Tamil Tiger rebel group based in the north seized territory from the breakaway 6,000-strong eastern faction, led by a charismatic commander Vinayagamoorthy Muralitharan, known as Karuna.
The two sides had been squared off since Karuna announced the schism March 3 in a dispute of regionalism rivalry and political strategy.
The fighters led by Kumar, one of Karuna's breakaway commanders, seemed calm as they checked their weapons and ammunition. They boarded tractors taking them and their rocket launchers, grenades, and heavy machine-guns to their new defensive line and announced they were closing the road for the night.
"We will fight to the last," said Kumar, carrying a light machine-gun as he hopped on the last of three tractors.
For two decades the Tamil Tigers fought government troops in a bloody separatist conflict that claimed an estimated 65,000 lives.
More than 3,500 terrified villagers had fled their homes by yesterday evening and more were planning to come, they said. Among the refugees was Sumitra, 28, carrying her month-old baby boy.
"I had thought that we can live like normal people, but it looks like we are refugees again," she said. Millions of people have been displaced in Sri Lanka's years of war.
Norwegian monitors said the reported civilian death and the wounding of seven others was already a breach of the cease-fire.
Amid fears that the peace process could be doomed if government troops were drawn into the fighting, President Chandrika Kumaratunga ordered her commanders to help evacuate rebel casualties from both sides, but not to interfere in their conflict, an official in her office said.
The army positioned men along the roadways in the region and along the sea cliff to prevent any landing by the mainstream Tigers at Panichachankani, where refugees were being cared for by the international relief organizations UNICEF and OXFAM.
"When the civilian population is affected it breaches the cease-fire agreement," said Hagrup Haukland, deputy chief of a European truce monitoring team.
The fight yesterday was multipronged. Groups of heavily armed northern rebels also landed in boats at Kathiravelli, a coastal village about 9 miles from the river, and were trying to advance on Batticaloa -- the breakaway group's stronghold, military officials said.
To enter that area they would have to cross Sri Lankan government-held territory.
"We don't want to get dragged into this," Defense Secretary Ciril Herath said after an emergency meeting with European cease-fire monitors in Colombo. "We are watching the situation very closely."
Police said at least four people in a minibus were wounded by a Claymore mine, a small device detonated remotely.