"Salim Allarakha Choukiya alias Ali (23), who had snatched a rifle from the police during the riots, was arrested from Anand Nagar area of suburban Oshiwara today," Ravindra Patil, assistant inspector at Oshiwara police station, said.
Salim could be seen firing a self-loading rifle seized from a policeman, Patil said, adding, "The accused claimed he had abandoned the rifle at the spot before escaping from there and did not fire."
Video footages of the Azad Maidan violence available with the investigators showed a section of protestors firing SLRs in the air.
"We are still to recover a pistol and some bullets missing since the Azad Maidan violence. We have visuals of some people who snatched firearms from police and fired in the air," said a crime branch official, who is the part of the Special Investigating Team probing the case.
Two SLRs, 150 rounds of ammunition and a service pistol of a police inspector had been looted by the mob. The police had later recovered the two SLRs and 29 rounds of ammunition.
Investigators are trying to trace the protesters featuring in the videos carrying guns and have detained five suspected rioters with injury marks. The role of the five in the riots is being ascertained, sources said, adding they have admitted to have been present during the violence but claimed to be innocent.
As hammers, knives and empty cans, said to be used to carry kerosene, and a pistol that did not belong to police were seized from the spot after the rioting, the police suspect the violence was pre-planned. They are also probing if the death of two persons during the violence was caused due to firing by the unruly mob.
Two youths were killed and 52, including 44 policemen, injured last Saturday when a rally called to protest alleged atrocities on Muslims in Assam and Myanmar turned violent.
The protesters went on the rampage, attacking the police, including some women constables, torching media and police vehicles, smashing cameras of photo journalists and damaging buses.
A day after the riots, the police had arrested 23 persons in connection with the incident.