Nurdin Hasan, Banda Aceh – Police have named three suspects, including a local councilor, in Friday's attack on a Muslim preacher and have detained two of them, an officer said on Sunday.

Zulkifli, 28, and Mukhtaruddin, 42, were detained for attacking Saiful Bahri as he delivered a sermon during Friday prayers at Keumala Grand Mosque in Pidie district. They were reportedly angered after the victim touched on the sensitive topics of the separatist Free Aceh Movement (GAM) and local politics.

"They didn't admit to the beating during questioning, but based on witness accounts they were named suspects. The two are now being detained," said a Pidie Police officer, Adj. Comr. Jatmiko. "The crime is punishable by up to five years in jail."

However, the police will need the governor's permission to detain the third suspect, Ilyas Abubakar, who is a member of the legislative council in Pidie. Ilyas is from the Aceh Party, a party founded by former GAM members and which controls the Pidie Legislative Council.

Jatmiko said the provincial police had been contacted about obtaining permission from the governor to detain Ilyas. More suspects could be named, the officer said, as witnesses have described more than four people assaulting Saiful.

Reports said the attackers were former members of GAM but Jatmiko would not speculate on any possible affiliations. "We are investigating a violent attack, that's all," he said.

Friday's violence in the mosque was condemned by local clerics, who called in an affront to Islam.

"An attack on a preacher over a prayer message is uncivilized and inhuman," said Teungku Faisal Ali, the head of the Aceh branch of Nahdlatul Ulama, the country's largest Muslim organization. "A sermon must not be disputed because it is part of the prayer."

Saiful, 35, angered some people in the mosque by criticizing local politicians and former GAM guerillas.