At least four persons were gunned down while two sustained critical injuries here in Natha Singh Street on Jinnah Road early on Thursday morning before dawn, a private TV reported. According to police sources, unknown armed militants opened indiscriminate fire in Natha Singh Street on Jinnah Road here which, resulted in sudden death for two persons, identified as Sahahzad and Naveed, while four critically injured persons were rushed to hospital wherein two wounded, Rauf and Asif, succumbed to injures. Top police officials arrived on the firing scene shortly after the incident and the a large number of relatives and friends stormed into hospital and staged protest demonstration for the early arrest of the offenders involved into killing, sources added.