One person was killed and four injured in a crane accident at a quake-hit nuclear power station in Japan, and four others were injured in a blast at another stricken plant nearby, the IAEA said.
The UN's nuclear watchdog said it had been informed by Japanese authorities that the worker was killed and four others injured in a "crane operation accident" at Fukushima No. 2 power plant on Japan's east coast.
The agency said that at Fukushima No. 1 power plant, which suffered an explosion yesterday a day after the massive quake, and where authorities are battling a feared meltdown of two reactors, eight workers had been affected.
"Four workers were injured by the explosion at the Unit 1 reactor, and there are three other reported injuries in other incidents," the IAEA said on its website, citing Japanese authorities.
"In addition, one worker was exposed to higher-than-normal radiation levels that fall below the IAEA guidance for emergency situations," it said, without giving further details.
About 200,000 people have been evacuated from residential areas around the Fukushima No. 1 plant and No. 2 plant, 250 kilometres (120 miles) north of Tokyo.
Japan's top government spokesman said it was highly likely a meltdown had occurred in one reactor of the Fukushima plant and that it was working on the assumption that one may occur in another.
The IAEA said it was working with the World Meteorological Organization to give weather forecasts for the affected areas.
The latest predictions suggested northeast winds would be blowing away from the coast for the next three days, it said.