Jakarta – Ethnic violence in Indonesian Borneo claimed another five lives, police and the military said Wednesday, a month after similar bloody clashes there left at least 500 dead.

"Four Madurese migrants were killed as they returned to their home in Saka Mangkahati village early in the morning yesterday [Tuesday]," Lieutenant Colonel Arie told AFP from Central Kalimantan province. Four other people were injured.

Arie said those killed and injured had previously been evacuated to neighbouring South Kalimantan province. But they had tried to return to their homes to salvage some of their possessions, he said.

Additionally, the Antara news agency reported from Palangkaraya, the capital of Central Kalimantan, that the headless body of a man had been found on a street there early Wednesday. The identity of the victim remained unknown.

The new toll brought to at least 15 the number of people killed in the latest wave of ethnic unrest involving indigenous Dayak tribesmen and Madurese migrants in the Kapuas district of the province.

Meanwhile, Kapuas district police late Tuesday freed five Dayak tribesmen arrested for involvement in last month's bloody ethnic violence, in which most the dead were also Madurese settlers.

District police chief Adjunct Senior Commissioner Saiful Maltha stressed, however, that the cases against the five remained in force and they would face trial on charges related to attacks by Dayaks on Madurese settlements. Police are still looking for 15 other men who, Maltha had said, were rioters and provocateurs.

The police chief denied the release had been prompted by a demonstration at his headquarters by about 200 Dayak tribesmen on Tuesday. Tuesday's protestors had earlier picketed the local district parliament, where some of their leaders gave the authorities 48 hours to rid the districts of all Madurese migrants.

About 1,500 Madurese migrants had been sheltering in government-protected refugee centres, with most now evacuated to Banjarmasin, 40 kilometres to the south.

The Kompas daily said that while lawyers and the police were preparing to release the five suspects, bands of Dayaks had set fire to 10 houses and stalls left vacant by Madurese, although Maltha denied this.

Kompas also said that leaders of the various ethnic communities in East Kalimantan, one of four Indonesian provinces on Borneo island, had agreed on Tuesday to form five teams to promote peace among ethnic groups. "These teams are tasked with finding the root causes of the conflict so far," Awang Faisjal, an East Kalimantan community leader was quoted as saying.

Tenisons between the two communities first erupted in Sampit on February 18 and quickly spread to Palangkaraya and Kualakapuas.

More than 50,000 Madurese have fled or been evacuated from the province. The clashes have been blamed on cultural differences between the two communities and the dominance of the Madurese in the local economy.