S Ramireddy allegedly attacked his wife Ramanjali (25) and son Teja with a pestle (kitchen utensil made with wood) while they were asleep, Poddili Circle Inspector B Ravi Chandra said.
The mother-son duo died on the spot. Prima facie, a family dispute could be the reason behind the killing, the officer said.
The accused escaped from the spot and efforts are on to nab him. A case under relevant sections of IPC has been registered with the Konakanametla police station and investigations are on, police said.