Vijender (32) came to the police station around 3 pm and informed police about the incident, following which he was arrested, a police official said.
The accused thrashed Inder Pal Singh (80) with a stick and then suffocated him to death using a pillow, the Deputy Commissioner of Police (Southwest) said.
Singh had lodged a police complaint over a property dispute following which his son-in-law and grandson were arrested. Vijender recently come out on bail and was angry with his father-in-law over the whole issue, police said.