TOKYO (Kyodo) -- About 150 U.S. nationals including sailors have filed a damages suit against Tokyo Electric Power Company Holdings Inc. seeking $5 billion in compensation for radiation exposure following the 2011 nuclear crisis in northeastern Japan, the company said Thursday.
The lawsuit was filed at a federal court in California by U.S.-based residents including personnel involved in the U.S. forces' Operation Tomodachi relief efforts following the massive earthquake and tsunami on March 11, 2011, that crippled the Fukushima Daiichi nuclear plant operated by Tepco.
The plaintiffs are seeking the establishment by Tepco and a U.S. company of a compensation fund to cover medical treatment and other related costs, the utility said without naming the company involved.
In Operation Tomodachi, which began two days after the earthquake and tsunami, the aircraft carrier Ronald Reagan and other U.S. military resources and personnel were employed to deliver supplies and undertake relief efforts.
After tsunami waves hit the six-reactor plant and flooded power supply facilities, reactor cooling systems were crippled and the Nos. 1-3 units suffered fuel meltdowns, resulting in the world's worst nuclear disaster since the 1986 Chernobyl crisis.
Tepco said the suit was filed on Aug. 18 local time.
The utility said it has not yet received documents on the lawsuit and will examine the details and respond appropriately.
The plaintiffs claim the nuclear disaster was caused by the improper design and management of the plant by Tepco. They are also seeking compensation for physical and mental damage suffered as a result of the disaster.
The plaintiffs are also seeking to combine their lawsuit with another filed in 2012 with a U.S. federal court in San Diego by a group of former U.S. sailors, who are suing Tepco for health problems due to radiation exposure during the relief operation.
The sailors argue they were exposed to radiation and suffered injury because Tepco misled them about the scale of the nuclear disaster.
The 2012 case was the first lawsuit against the utility filed with an overseas court in connection with its handling of the nuclear crisis.