Angela Tresnasari, Jakarta – Indonesia's military said on Monday it had arrested 30 soldiers in the restive province of Aceh for beating to death and torturing suspected separatist rebels at the weekend.

"I say this firmly – I cannot justify what happened on Saturday. I will investigate the incident thoroughly and send the suspects to the military court by the end of the month," Lhokseumawe military commander Johny Wahab told Reuters.

Military officials and human rights groups said on Sunday that four people died after troops attacked villagers who were detained in a raid on a village suspected of harbouring rebels. Yakob Hamzah of the respected Lhokseumawe Legal Aid Institute said three people were still missing after the incident and 26 in hospital.

"We are not sure if the three people are missing or killed. We cannot find them in the hospital. So, we are still searching for those three," he told Reuters. "There are about 26 people in hospital who were badly injured while three of them are in a critical condition."

Troops in the staunchly Moslem, resource-rich province have been hunting for an alleged separatist leader called Ahmad Kandang, who they accuse of masterminding a recent upsurge in attacks on police and the military.

Wahab said the armed forces early on Saturday raided Kandang village near Lhokseumawe, an industrial town on the northern tip of Sumatra some 1,600 km northwest of Jakarta, to try to capture the separatist leader.

He said rebels fired at the troops during the raid and used women and children to shield themselves. "We did not shoot back because of the women and children," Wahab said.

Kandang was not found, but Wahab said 40 people suspected of being his followers were detained for questioning and many of them were carrying pistols and other firearms. Yakob said these detainees were later attacked and tortured by soldiers.

In late December a mob of machete-wielding villagers dragged off-duty soldiers off a public bus. Six were tortured and killed and two other soldiers are still missing.

On January 3 several civilians were killed when security forces and separatists exchanged gunfire during a protest by a mob of thousands who attacked government buildings near Lhokseumawe. The Legal Aid Institute says 17 died, while the army puts the toll at 11.