Japanese officials have found a small area in Tokyo with higher levels of radiation than evacuation zones around the Fukushima nuclear plant.
Tokyo's Setagaya city's mayor says concerned parents monitoring for radiation asked them to conduct further tests on a roadside spot near a kindergarten. Its radioactivity slightly exceeded that of an area about 25 miles (40 kilometers) from the Fukushima Dai-ichi plant.
Mayor Nobuto Hosakai says the cause is being investigated. He says rainwater containing radioactive particles had been dripping from the roof of a building by the sidewalk.
Officials said Wednesday that an estimated annual exposure at the spot wouldn't pose a health danger. They say the area has been closed off and city officials will also survey nearly 260 parks.