The National Investigation Agency probing the violence in the city last month on Thursday said it conducted searches at 30 places here and arrested a key conspirator, who was absconding.
Identifying the arrested as Sayed Saddiq Ali, a recovery agent with a bank, the agency said he was absconding since August 11 when over 3,000 people went on a rampage torching the residences of Congress MLA R Akhanda Srinivasa Murthy, his sister Jayanthi and Devara Jeevanahalli and Kadugondanahalli police stations.
The action came days after the NIA took over the investigation into two cases in which the city police has invoked the Unlawful Activities Prevention Act.
A mob rampaged through Bengaluru's Pulakeshi Nagar and vandalised a police station and a Congress legislator's residence after an alleged relative of the MLA shared a social media post purportedly on a communal issue, police said.
A large number of people gathered near MLA Akhanda Srinivasa Murthy's residence and vandalised it and damaged the vehicles parked there.
The mob then targeted the police station and damaged vehicles believing that the police had kept the accused detained there, they said.
The police teams that tried to contain the violence also bore the brunt of the mob as their vehicles were damaged, eye-witnesses said.
Police sources said a person said to be a close relative of Murthy allegedly shared a social media post that enraged members of a community.
Home Minister Basavaraj Bommai said riots and arson are against law and warned the rioters that he has given police a free hand to contain the violence.