OSAKA (Kyodo) Three members of a family of four were found dead in the gutted remains of a two-story wooden house in Kawachinagano, Osaka Prefecture, late Thursday in a fire that may have been caused by a kerosene heater, police and firefighters said early Friday.

Police identified the bodies as those of company employee Kiyoshi Sato, 68, and his sons, Tadashi and Makoto, both 37.

The fire occurred at around 11:45 p.m. at their house, burning about 110 sq. meters.

Police said Sato’s wife, Saki, 65, fled the fire and was found safe.