Ligature marks caused by strangulation were found on her neck, they said, adding her son-in-law was a suspect in the murder.
"It is suspected that the son-in-law of the deceased, Shanti Devi, killed her over a property dispute as he is missing," police said.
A case of murder has been registered at Narela police station and efforts are on to arrest the culprit, said a police officer.
The victim was a widow and had four daughters. One of her daughters and her husband Awadhesh Kumar lived with her. The suspect was allegedly pressurising the elderly woman to make him the owner of the house, police said.
In the morning, when Shanti Devi's daughter came out she found her lying dead in the bed while Awadhesh was nowhere to be found, the officer added.