Lucknow, Dec 7 : A sub-inspector of the Uttar Pradesh Police has been detained for questioning after a woman, whom he was in a live-in relationship with, was found dead in mysterious circumstances in her flat in the Chinhat area. The incident happened on Sunday. The woman, Mamta, was living with Rahul Rathore, sub-inspector in the Uttar Pradesh Police, currently posted in Lalitpur district. Assistant Commissioner of Police (east) S.M. Qasim Abdi said the forensic team found a pistol and letter from the spot. "Whether it is murder or suicide will be ascertained once we get the post-mortem report. The sub-inspector and his servant are being questioned," he said. Chinhat Police Station inspector Dhananjay Kumar Pandey said the body had a gunshot wound. The duo was staying together for the last four months. It is also being probed whether Rathore took a leave to come to Lucknow or was absent from duty, police said. /IANS