Pyongyang, August 6 (KCNA) -- Radiation leakage at the crippled Fukushima Nuclear Power Plant in Japan is getting serious.

Tokyo Electric Power Co. on Tuesday said radiation dosages of 5 sieverts per hour were detected indoors on the second floor of the No. 1 reactor at the plant.

The amount is the highest figure for indoors which has so far been measured within the buildings of reactors Nos. 1-4, a news report said.

On July 28 the Ministry of Health, Labor and Welfare noted that radioactive cesium above the permissible limit was detected in a total 1 557 tons of soils which were settled when water was being filtered at the purifying grounds in Miyagi, Fukushima, Niigata, Tochigi and Gunma prefectures.