The charred bodies of the three 55-year-old Akshyaya Pattnaik, his 30-year-old son Kalindi and 22-year-old daughter were found in their beds though other furniture was unaffected in the room at their home at Talagaon village, about 20 km from here under Patkura police station, police sources said.
"From preliminary investigation, it is apparent that it was not a simple case of fire, but a planned murder by close relatives," Kartik Chandra Mallick, Inspector of Patkura police station, said.
The sources suspected that the victims were killed and their bodies burnt before being kept in the room.
"Circumstantial evidence indicate that the case could be a planned killing using kerosene oil," Fire Officer at Korua, Dolagobinda Sethi, said.
Four persons including the elder brother of Akshya were detained after sniffer dogs provided some clues, the sources said.
