Jakarta – A clash between police and machete-wielding members of a shadowy Islamic sect on Indonesia's eastern Sulawesi island has killed four people, three of them police officers, a senior policeman said on Wednesday.

The incident took place on Tuesday in the rugged hills just outside the Central Sulawesi provincial capital of Palu. Fighting broke out when police had sought to apprehend the leader of a tiny sect which was branded deviant by local Muslim clerics.

"His supporters became hysterical and started to attack officers when police were about to take him," said deputy national police spokesman Soenarko Artanto, adding one sect member also died in the fighting.

Local media reported police retaliated with guns after being attacked with lethal traditional weapons like machetes and poisonous blow darts.

Palu police chief Guntur Widodo told Reuters around 20 sect members were taken by police for questioning but the sect leader was still at large. Previously, Soenarko had said the leader, known only Madi, was in police custody.

On Wednesday, more than 300 police officers were deployed to guard the sect's remote hamlet.

Local mainstream clerics in Palu, which is 1,650 km (1,030 miles) east of Jakarta, said that although the sect considered itself Islamic, the followers mixed the religion with ancient local traditions and refused to observe basic Islamic tenets such as fasting during Ramadan or praying five times a day.

Muslims all over the world are observing the holy Ramadan month, which will end in early November.

Indonesia's Religious Affairs Minister Maftuh Basyuni called the sect, whose followers always wear white headbands and yellow scarves, "a very, very deviant group." Indonesia is the world's most populous Muslim nation, but groups branded as deviant periodically spring up.

Last month, hundreds of angry Muslims in West Java province torched more than 30 houses and damaged mosques belonging to a breakaway Muslim sect connected to the Ahmadiyah movement.