Director General of Police Gaurav Yadav on Friday visited the Bhagtanwala grain market, where Assistant Sub-Inspector (ASI) Harjit Singh was shot dead by motorcycle-borne assailants while on duty earlier in the day.Before visiting the crime scene, the DGP met the bereaved family of the police and expressed his condolences.Preliminary investigation suggests that the assailants followed the ASI and fired at him from close range. A bullet hit the back of his neck, causing fatal injuries. Police recovered a .30 bore bullet shell from the crime scene.Yadav reviewed the investigation and directed officials to examine all possible leads. Police Commissioner Harmanbir Singh Gill briefed him about the incident and the progress of the probe.The DGP said a technical investigation was under way and that CCTV footage from the area was being examined to trace the movements of the assailants before and after the shooting.Police teams have been deployed to work on the CCTV trail and other technical evidence to identify and arrest the suspects.