Inspector Vijay Singh was arrested after the family of former BSP legislator Sarvesh Singh, who was shot dead July 19 in Azamgarh, accused him of conspiring with criminals to kill the leader.
Acting on a complaint lodged by Santosh Singh, elder brother of the late leader, top police brass ordered the arrest of Vijay Singh. The family of the slain leader has named eight other people in the first information report (FIR).
Violence and arson had erupted in Azamgarh, 270 km from state capital Lucknow, after Sarvesh Singh's murder. In the subsequent police firing, two people were killed and over three dozen injured.
Three men on a motorcycle fired at Sarvesh Singh and his guard Bharat Rai a few metres away from a police station. His supporters had accused a police inspector of summoning him to the police station.
Sarvesh Singh had contested the 2007 state assembly polls on a Samajwadi Party (SP) ticket. He later joined the BSP and unsuccessfully contested the assembly polls last year from Sadar seat. He lost to SP's Durga Prasad.