Srinagar, An encounter ensued between militants and security forces during a Cordon and Search Operation (CASO) in south Kashmir district of Kulgam on Sunday morning, official sources said.They said troops of Special Operation Group (SOG) of Jammu and Kashmir police, Rashtriya Rifles (RR) and CRPF launched a joint CASO at Sighanpor, Kulgam following a tip-off about the presence of militants.After all exit points were plugged, when security forces were moving towards a particular area, militants hiding there opened indiscriminate firing with automatic weapons, they said adding security forces also retaliated ensuing in an encounter.The operation was still going on when the reports last came in, they said adding two to three militants were trapped in the area.Meanwhile, additional security forces and police personnel have been deployed in adjacent areas to prevent any law and order problem.