Security has been beefed up in the city in the wake of Sunday's incidents of violence involving supporters of two political outfits, police said.

"The sensitive pockets, where trouble can erupt, are on high alert. The cinema theatres have also been provided security as one of the movie halls, showing a Bhojpuri film was targeted on Sunday," police said.

Meanwhile, Samajwadi Party (SP) general secretary Amar Singh lodged an FIR against Maharashtra Navnirman Sena (MNS) chief Raj Thackeray in the wee hours on Monday, accusing him of encouraging attacks on North Indians.

Also, two unidentified persons hurled glass bottles in the direction of filmstar Amitabh Bachchan's residence early on Monday morning forcing the police to set up high security cover at his residence, they said.

Prior to the United National Progressive Alliance (UNPA) rally at the Shivaji Park on Sunday, MNS activists clashed with SP supporters, close to the venue resulting in detention of the violent mob.

Supporters of both the parties allegedly assembled outside the Plaza cinema in Dadar and indulged in stone pelting following Rajya Sabha MP and SP leader Jaya Bachchan's retaliation to Raj Thackeray's statement against her husband, Amitabh Bachchan.