SPO Pawan Kumar, working with police ran away from his duty and went to his in-laws's house in remotest Gandolo belt of Doda district and clashed with his wife and in-laws late last night, SSP Doda Arif Rishu told PTI.
In a fit of anger he opened indiscriminate firing from his rifle and killed his wife Champa Devi, mother-in-law Sumitra Devi and injured critically his father-in-law Desh Raj, SSP said.
Later, he attempted suicide by firing on himself, SSP added.
The injured father-in-law and SPO have been shifted to Jammu for medical treatment.
The post mortem of bodies was conducted and handed over to family members for the last rites, he said, adding, a case has been registered and further investigations are on.