Not good.

TOKYO — Japan faced the likelihood of a catastrophic nuclear accident Tuesday morning, as an explosion at the most crippled of three reactors at the Fukushima Daiichi Nuclear Power Station damaged its crucial steel containment structure, emergency workers were withdrawn from the plant, and much larger emissions of radioactive materials appeared imminent, according to official statements and industry executives informed about the developments. — NYTimes

[10:12 p.m. ET Monday, 11:12 a.m. Tuesday in Tokyo] A fire has erupted in a fourth reactor at the damaged Fukushima Daiichi nuclear power plant, a top adviser to Japanese Prime Minister Naoto Kan announced Tuesday. – CNN