Police said 28-year-old Abinash Patra, a junior constable in the district headquarters, went to his village in Gopiballabhpur block and fired on his parents on Sunday afternoon with his service rifle.
Hearing the shots, the villagers informed police, who came under firing when they surrounded the house.
Police asked Patra to surrender, but there was no response.
When they forced themselves into the house, they found bodies of the aged parents, and Patra.
Villagers said Abinash’s parents were looking for a match for him, which could have triggered a dispute.