By Lucy Williamson
BBC News, Jakarta
Hardliners allegedly beat people at a tolerance rally in Jakarta
A leader of one of Indonesia's hardline Muslim groups has told his followers to "prepare for war" after violent clashes with liberal Muslim demonstrators.
Habib Riziq heads the hardline Islamic Defenders' Front, or FPI, whose members allegedly attacked a rally in support of religious tolerance on Sunday.
The rally was called amid debate over whether the government should ban the minority Ahmadiyah sect.
Hardliners oppose the Ahmadiyah belief that Muhammad was not the last prophet.
Several members of Mr Riziq's group allegedly beat people at Sunday's rally in Jakarta.
Now, with the police under pressure to make arrests, the FPI is saying it will not co-operate.
The police have been criticised for not intervening firmly enough during the disorder, and for not making arrests on the spot. Now, they say, they are making up for lost time.
A police spokesman said officers were in the process of arresting five suspects, but he would not confirm which organisation they belonged to.
Differences between militant and liberal Islamic groups in Indonesia have crystallised this year around the issue of the Ahmadiyah - a few hundred Muslims in a country of 200 million.
A widespread belief among the minority branch is that another prophet came after Muhammad - a claim that has triggered calls for a government ban.