text: A playground in Tokyo has been found to have dangerously high levels of radiation, which has raised fears for the health of children in the area. Soil underneath a slide at the park in the Toshima ward in the north-east of the Japanese capital, showed radiation readings of up to 480 microsieverts per hour. This is nearly half the recommended annual limit of exposure for a person. Danger: Japanese authorities detected an unusually high level of radiation around playground equipment in this Tokyo park (pictured) Safety: Authorities cordoned off the park after high levels of radiation were detected underneath a slide . It was not immediately clear why radiation levels were so high in the park, which opened two years after the 2011 Fukushima disaster. Authorities believe that the radiation could be coming from something buried underneath the park. The playground has now been fenced off with an orange barricade. Park representative Kyoko Tsujimura said: 'We are still checking what caused these elevated radiation levels and what type of radioactive substance it is.' The city has set up a health advice office to answer queries from concerned parents. According to the International Commission on Radiological Protection recommendations, members of the public should not be exposed to more than 1000 microsieverts per year. Japan has seen heightened concern over radiation since the 2011 failure of a nuclear plant in Fukushima following an earthquake and tsunami, which led to leaks of radioactive water. In the months after the nuclear meltdowns, concerned parents and citizens began measuring radiation levels in Tokyo schools and parks. Thousands of people are still living in temporary shelters and have been unable to return home in areas closest to Tokyo Electric Power's nuclear plant. Elsewhere, a drone with a small amount of radiation was found on Japanese Prime Minister Shinzo Abe's office building this week. Clean up: Workers carry away a container after extremely high levels of radiation were detected in the park . Tests: Following two rounds of testing, officials found high levels of radiation on a section of the equipment .
target: Soil underneath a slide in the park showed extremely high radiation levels .
  Has raised fears for the health of children in the Toshima ward of Tokyo .
  Days after traces of radiation found at Prime Minister Shinzo Abe's office .