Bengaluru police have zeroed in on the person who sold a country made pistol to Mahesh, the man accused of killed 17-year-old Gautami.A team of police personnel went to Bihar, to verify Mahesh’s claims that he purchased the weapon from a man from Mungur district. Upon contacting the Bihar police, the Bengaluru cops were able to trace the man and learned that the Bihari man had sold the weapon to Mahesh four years ago, as he needed Rs 6,000 at the time.Mahesh kept the weapon all these years. Police claim that Mahesh decided to kill Gautami as she insulted him publicly.