Rajesh, whose father Bharat Singh had established a live-in relationship with his mother-in-law and a widow Laxmi Devi, had developed a grudge against her, following which he killed the 45-year-old woman in collusion with his cousin Sanjay, they said.
The decomposed body of Laxmi was recovered by police from Garhi Bolni village near Kasauli on August 13.
However, later, police registered a murder case against the duo on August 31, based on a complaint filed by Bharat Singh.