Chandigarh, Sept. 20 -- The main accused in the killing of Assistant Sub-Inspector Harjeet Singh was killed in an exchange of fire with police in Amritsar, while a second suspect escaped under cover of darkness, Police Commissioner Harmanbir Singh Gill said.

Gill said police had intensified checking across Amritsar following the killing of Harjeet Singh, who was shot dead while on duty on September 18. Police had received information that the suspects were moving in the area and could be looking for another target, he said.

During a checkpoint operation, a police team signalled two men travelling on a scooter to stop, but they allegedly opened fire instead, Gill said.

Police chased them, who abandoned the scooter and again fired at the p...