A boiler in a women's spa in central Tokyo exploded Tuesday, killing one woman and injuring at least four others. At least one other person was believed to be buried in the wreckage.
Police said one person was dead. The victims suffered burns, fire officials said. A second woman's heart and lungs had stopped functioning, but she has not been declared dead.
The afternoon explosion was caused by a malfunction in the boiler in the one-story annex of the popular "Shiespa" bathhouse, said police official Junko Tada. The main building apparently did not sustain major damage, but was being examined by officials.
Police and fire officials said four people had been confirmed hurt in the explosion. Police could not confirm the age or sex of the dead person.
After the flames had been extinguished, fire officials swarmed the blasted shell of the building, which was destroyed except for the mangled iron frame. Debris had been blown in to the street and against the neighboring apartment houses, shattering windows.
At least one person was missing and believed buried in the rubble of the building, said fire department official Yuji Kohara. The person may have been in the basement of the building at the time of the blast.
"I heard a sudden huge boom. When I jumped outside, I saw a plume of smoke," said Miki Yamagishi, a clerk at a nearby convenience store.
About 100 rescuers used search dogs to scan the debris. Two other passers-by were slightly hurt, according to broadcaster Nippon TV.
Shiespa is a women's only spa in central Tokyo with a natural hot spring, an open-air bath, a sauna and salon, according to its Web site.