Police launched an investigation into the cause of the fire on the fourth floor of the eight-storey building for suspected arson, local sources reported.
The fire broke out on the fourth or fifth floor. A psychiatry clinic is located on the fourth floor. The Yomiuri newspaper said an old man brought a bag with leaking flammable fluid into the building.
Dozens of firefighters rushed to the building and the blaze was brought under control in thirty minutes.
The firefighters said the blaze engulfed an area 20 meters square, and that seventy fire trucks and ambulances rushed to the scene. (ILKHA)