Five of the 16 named in the FIR have been arrested in connection with the Haldwani violence that killed 6 and left 60 injured.
Police said that they have launched a manhunt to trace Abdul Malik, the man who built the "illegal" madrassa, whose demolition triggered violent clashes.
"The police have begun a search for an accused named Abdul Malik who had built the now razed illegal structure and opposed its demolition most strongly," Nainital Senior Superintendent of Police Prahlad Meena said at a press conference, reports PTI news agency.
CCTV footage and video clips of the incidents of Thursday collected from different sources are being analysed to identify the rioters, the police said.
The police further said that internet services will remain suspended in the violence-hit Banbhoolpura town to prevent rumours from spreading through social media platforms.
Shops on the outskirts of the town opened on Saturday following the partial lifting of the curfew but schools remained closed.
Meanwhile, the government has launched a magisterial probe and a report will be submitted in 15 days.
About the people killed in the violence, the SSP said no one died in the police firing and a post-mortem will clarify the circumstances of their death.
"No one died in the firing as we had searched the entire area after the firing and found no bodies. The bodies were found the next day in hospitals. Post-mortem and forensic examination reports will clarify the circumstances that led to their death," he said.
(With PTI inputs)
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