Police said that security has been stepped up in the city in the wake of Sunday’s incidents of violence involving supporters of two political outfits. Police said that the cinema theaters have also been provided security as one of the movie halls, showing a Bhojpuri film was targeted yesterday. Also, two unidentified persons attacked film star Amitabh Bachchan’s residence by glass bottles early this morning forcing the police to set up high security cover at his residence, police said.