An anonymous phone call was received at the office of film director Maniratnam here, saying a bomb would go off in its premises if some dialogues in his latest movie Chekka Chivantha Vaanam were not removed, police said Tuesday. Police are yet to trace the person who had issued the threat Monday night. Following the call, the staff at the office-Madras Talkies-lodged a complaint, the police said. The film was released on September 27 with music scored by two-time Oscar winner A.R. Rahman.