Srinagar, Oct 21: Three militants were killed in an encounter with security forces in Kulgam district of Jammu and Kashmir Sunday, police said, adding six civilians lost their lives in a blast after the gunfight ended.The identity of the slain militants is being ascertained, a police official said.Security forces launched a cordon and search operation in Laroo area of Kulgam district in south Kashmir following specific information about the presence of militants in the area, he said.As the forces were conducting the searches, the ultras fired upon them, triggering the encounter, the official said. Six civilians were also killed in a blast at the encounter site after the forces had withdrawn from the spot."Civilians visited the encounter site immediately after the operation in spite of (our) request not to go there as a thorough search is to be made for explosives once flames douse. They did not listen and visited the spot immediately after the forces withdrew."Some explosive substance went off, resulting in injuries to civilians. One civilian namely Ubaid Laway, a resident of Laroo, died on the spot," the police official said."The others injured in the incident were rushed to a hospital, while few were referred to SMHS Hospital, where two of them succumbed to injuries," he said.Later three more injured died.Meanwhile, clashes broke out between groups of youths and security forces in the area."Police had to use some force to quell the protests and around two dozen persons were injured in the clashes," the official said.Kulgam MLA and CPI(M) leader M Y Tarigami expressed grief over the loss of civilian lives and demanded a probe into the incident."It is devastating. This needs to be investigated through an impartial probe...We are now tired of crying and demanding, but those who matter have turned a deaf ear," he said.Advisor to the Governor, K Vijay Kumar, and DGP Dilbag Singh also expressed regret over the loss of civilian lives.A police spokesman said encounter sites should be avoided by civilians till they are properly sanitised.