On 26 April 1986, reactor # 4 at the Chernobyl (Chornobyl) Nuclear Power Station, 100 km north from Kiev, blew up during a routine daily operation. Nearly nine tons of radioactive material - 90 times as much as the Hiroshima bomb - were hurled into the sky. Winds over the following days, mostly blowing north and west, carried, fallout into Belarus, as well as Russia, Poland and the Baltic region. The radioactive fallout affected 23% of Belarus, with 4,8% of Ukrainian territory and 0,5% of Russian land exposed. About 135,00 people were evacuated from a 30-km radius around the plant, with the peripheral areas remaining at a high risk of radioactive exposure. The reactor was enclosed in a concrete-and-steel sarcophagus. Over the following years about 600,000 people known as "the liquidators" worked on clean-up operations inside the 30-km zone. Although scientists agree that there is no risk of the sarcophagus exploding, the status of the estimated 180 tons of radioactive material trapped inside the nuclear power plant is still unclear.