Police on Sunday arrested 23 people on charge of murder in the violence in Mumbai on Saturday in which two persons were killed and 55 people, including 46 policemen, were injured, which appeared to be a "pre-planned" act.
Besides the 23 people, who were booked under section 302 of IPC, the organisers, Raza Academy and Madina Tul Ilm Foundation, also faced similar charges, police said.
The accused were produced in a local court on Sunday which remanded them in police custody till August 19.
What prompted police to suspect that the violence was pre-meditated was that the word about the event was spread through Facebook, sources said, adding that the investigators might rope in the Cyber Crime cell to find out who posted the online messages and sent the SMSes.
Police suspect the violence to be a "pre-planned" act as participants at the Azad Maidan rally came "prepared" to wreak havoc.
As rioters carried sticks and rods with them, police are now probing from where the weapons were procured and where they were stored before the trouble started. "We are also investigating the source of petrol cans. The mob set the vehicles on fire in a much planned way," a police official said.
According to police, the CCTV footage showing the protesters pouring petrol on vehicles before torching them has been obtained and would be examined.
A special team of Crime Branch, headed by an Assistant Commissioner of Police and consisting of 12 officers, will conduct the investigations.
The rally, held on Saturday afternoon at Azad Maidan in south Mumbai to denounce riots in Assam and also the alleged attacks on a minority community in Myanmar, turned violent with the mob pelting stones, torching vehicles and damaging buses, forcing police to open fire in which Mohammed Umar (22) and Altaf Shaikh (18) were killed.
A war memorial outside the BMC office was also vandalised in Saturday's incident.
Meanwhile, two police rifles snatched away by the mob from police personnel yesterday were today found dumped, along with 19 rounds out of 160 rounds stolen, at Amritnagar in Mumbra, in neighbouring Thane district, police said.