Now Playing:Japan races to restore cooling at nuke plant
Description: Time is running out for emergency workers in Japan seeking to restore electricity to the quake-stricken Fukushima nuclear plant to re-power the reactor's cooling systems and prevent a meltdown. Officials at the Nuclear Safety Agency have raised the severity of the nuclear crisis unfolding at the plant damaged in last Friday's magnitude 9.0 earthquake from 4 to 5 on a 7-level international scale. Tokyo Electric Power Company said it was hoping power would be back on at two of the plant's six reactors by Saturday to avert a disastrous release of radiation. Attempts on Thursday to connect a one-kilometer long power cable from the grid to the plant failed due to the extent of the damage caused by this week's series of explosions in the reactor buildings. The company also said it may consider the option of encasing the plant in concrete, but plans to first focus on cooling the facility. In a nationally-televised address on Friday, Japan's Prime Minister Naoto Kan sought to assure the public that Japan was capable of overcoming the worst crisis that it has faced since World War II. Kan addressed the nation shortly before officials, emergency workers and evacuees observed a moment of silence in the devastated prefectures of Fukushima, Miyagi and Iwate, marking the time the quake struck. Earlier on Friday, smoke was reported to be rising from reactor 2, after some 64 tons of water had been sprayed on the reactors. More fire trucks continued to deliver water to cool the ...