Steam rising from reactor building at Fukushima nuclear plant

TOKYO – Steam or vapors appeared to be coming from a damaged reactor building at Japan's tsunami-crippled nuclear plant Thursday, but the plant operator said radiation levels were steady.

The video images showed a small amount of vapor or steam but the origin wasn't clear. Tokyo Electric Power Co. said the reactor's spent fuel pool is stable and measurements of the temperatures and pressure have not changed significantly.

Workers were continuing to inject water into the No. 3 reactor to cool it, the utility said.

The No. 3 reactor was one of three at the Fukushima Dai-ichi plant that suffered core meltdowns after the 2011 earthquake and tsunami, leading to the world's worst nuclear disaster since Chernobyl in 1986. Thousands of people have been unable to return to their homes near the plant because radiation levels are still high.

Most of Japan's nuclear reactors remain shut down for safety checks following the disaster.