A soldier allegedly opened fire on his parents, injuring both, following a domestic dispute at their residence at Jogi Nagar here on Thursday night.The accused, identified as Harpreet Singh, is reportedly under mental stress and had come home on leave.Sources said Harpreet first had an argument with his father, Daljit Singh, and mother, Paramjit Kaur. As the dispute escalated, he allegedly fired at them with his licensed pistol. He also reportedly assaulted his father during the altercation.Daljit Singh sustained serious injuries and was initially taken to the Civil Hospital. He was later shifted to a private hospital, where he is undergoing treatment. Paramjit Kaur was also injured in the firing.Inspector Harjot Singh, SHO, Canal Colony police station, said an FIR was being registered on the complaint of the injured.“We received information about a firing incident at Jogi Nagar. Preliminary investigation revealed that the accused had a dispute with his parents. We are verifying the firing,” he said.