One of the accused in the killing of Assistant Sub-Inspector (ASI) Harjit Singh was shot dead in a police encounter in the Islamabad area here on Saturday night.The deceased was identified as Deepak Singh, a resident of Mulechak village.ASI Harjit Singh was shot dead while on duty in the Bhagtanwala grain market area under the Gate Hakima police station in the intervening night of Thursday and Friday.Related news: Punjab ASI shot in fourth targeted attack on copsThe police said CCTV footage, technical inputs, tower-dump analysis and information gathered from local sources during the investigation helped identify Deepak as one of the suspects.According to the police, around 9.45 pm on Saturday, a police team signalled two suspects travelling on a scooter to stop at a naka. The suspects allegedly opened fire at the police party and fled towards another checkpoint.The police said the suspects again opened fire at the subsequent naka, firing four rounds, following which the police retaliated in self-defence.During the ensuing exchange of fire in the Islamabad police station area, Deepak sustained gunshot injuries. He was rushed to a hospital, where he later succumbed to his injuries.The police claimed to have recovered a .30-bore pistol, two magazines containing eight live cartridges, a mobile phone and an Activa scooter allegedly used in the crime. Further probe is under way.