Two persons, including a temple priest, were killed at a village in neighbouring Deoria district on Monday, police said. The body of a local Shive temple priest Moti Yadav (70) was found near a lake in Sakrapar village under Sadar Kotwali police station area this morning, police said. Injury marks were found on Yadav's body. Convinced that temple guard Pintu Patel (25) committed the murder, Yadav's family members killed him with sharp-edged weapons, police said. SP Deoria, N Kolanchi said Pintu Patel was a mentally unstable person who had been attacking unsuspecting persons in the last 4 to 5 days. Patel allegedly killed Yadav and the latter's family members, retaliated by killing the temple guard, the official added. "We have detained one Sunil Yadav in connection with the murder of Pintu. He told us about the involvement of four other relatives of Moti Yadav. Efforts are on to nab the accused," the SP said, adding that the bodies have been sent for post-mortem examination.