The bodies were found in the house in Chotapurwa locality by neighbours. Police suspect the attack took place late on Tuesday.
A son and daughter of the couple survived as they were able to hide, an official told IANS.
The survivors have named a distant relative as one of the assailants. The police are trying to recreate the crime scene to identify the attackers as per the description available, and arrest them, the official said.
The deceased have been identified as Mahadev Yadav, his wife Chunni and their two sons aged 10 and 8.
The bodies have been sent for post-mortem and the survivors have been taken to an undisclosed location.