Nambardar Piara Singh, who was suspected of murdering a 50-year-old widow at Cholti Kheri village, committed suicide by hanging himself from a ceiling fan at his residence, they said.
The widow, Jaspal Kaur, was found murdered in a car on the outskirts of Cholti Kheri village on Tuesday.
On the basis of a statement of the widow's son Gurpreet Singh, police had registered a case against Piara Singh.
Gurpreet had alleged Piara Singh had kidnapped his mother and later killed her.
Police had found Piara Singh's mobile phones from the car.