ACB's Superintendent of Police Sandeep Karnik said that the complainant's cousin brother was arrested by the Murbad police in connection with a criminal case and was in police custody for some days.
Allegedly, Assistant Police Inspector Rajendra T Hulawale (45) demanded Rs 50,000 from the complainant, whose brother was still in the custody, for not extending his police custody and favouring him in the case.
An offence under Prevention of Corruption Act has been registered against the official at the Kalamboli police station in Navi Mumbai, ACB officials said.