He said around the same time JCO Subedar Major Goor Singh of 22 RR entered the room and tried to control Naik Satinder Singh but Satinder shot him dead too.
Lance Naik Anand Singh and Omi Singh were identified among those killed in the firing.
Naik Sanjay Singh was shifted to hospital.
A convoy of army jawans had come from Kargil on temporary duty to the Jammu army camp on Friday.
A court of inquiry has been ordered by army authorities to ascertain the reasons behind the incident, he said.