Indonesian troops fanned out in thick jungle and villages across Aceh yesterday in search of rebels. Earlier the military said it had killed four separatists overnight, taking the total since Monday to 12.
A spokesman for the Free Aceh Movement (GAM) insisted no separatists had been killed and accused the military of murdering nearly 50 civilians. The military denied killing non-combatants.
Senior officers said they were considering imposing night curfews in areas hit by the heaviest clashes.
In Jakarta, Foreign Minister Hassan Wirajuda went on the defensive in the face of international concern over the military's biggest offensive in decades, launched on Monday following the collapse of weekend peace talks.
He told foreign envoys Indonesia's territorial integrity was at stake over Aceh, the country's northernmost province on the tip of Sumatra.
"GAM forces are moving continuously, and we are tracking them today," senior military spokesman Lieutenant Colonel Achmad Yani Basuki said. "Our attacks are not on specific areas, but wherever we find GAM. In those places, we will carry out attacks."
Casualty claims have been hotly disputed ever since GAM began fighting for independence in 1976.
But one hospital official in the provincial capital, Banda Aceh, said the military had brought in nine dead bodies riddled with bullets since Monday, whom he said looked like civilians.
"Almost 50 civilians have been killed by the military," said a GAM spokesman, speaking from an undisclosed location. He could offer no eyewitness accounts of troops doing the killing.
The military said it had killed 12 rebels and captured nine in the campaign so far, for the loss of six soldiers wounded. There were no immediate reports of clashes yesterday.
The military said a district rebel commander had surrendered on Wednesday, coinciding with the bloodiest clashes since President Megawati Sukarnoputri declared martial law here.
They said Teuku Ali Said, rebel chief of a district in western Aceh, gave himself up to Indonesian soldiers. Last week a more senior rebel commander defected.
Officials said schools were still being burned down in this resource-rich province, with about 250 schools torched since Monday, affecting 60,000 students. The two sides have traded accusations over the arson, and the military has threated to shoot perpetrators on sight.
Public transport on the main road linking Banda Aceh and the capital of neighbouring North Sumatra province has ground to a halt following attacks on vehicles, officials said.
More than 10,000 people have been killed in the 27-year war.
Foreign Minister Wirajuda said the rebels alone had wrecked the peace process. Mediators have said Jakarta sank talks in Tokyo aimed at saving a five-month-old peace pact, saying it had sought to impose new conditions on the rebels.
"Nothing less than the sovereignty and territorial integrity of Indonesia is at stake ... It is they who speak the language of force and terror," said Wirajuda.
"The Indonesian government and people are doing only what are expected of us, we are confident that governments around this hall would do the same if faced by a similar challenge."
Aceh is one of two separatist hot spots in Indonesia. The other is Papua province in the far east.
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