Number three reactor explodes. number four on Fire, at Japan nuke plant, radiation rises.
Not long after the number three reactor exploded, a fire has broken out at the number-four reactor at the quake-hit Fukushima No. 1 atomic power plant and radiation levels have risen considerably, Japanese Prime Minister Naoto Kan said Tuesday.
People between 20-30 km from reactor should stay indoors, Kan said.
