TOKYO - Tsunami warnings for the northeast coast of Japan issued after a strong earthquake late on Thursday have been lifted, NHK public television reported on Friday.
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Earlier Thursday, a major earthquake shook the northeast of Japan, prompting the tsunami warning which was issued for the coast already devastated by last month's massive quake and tsunami that crippled a nuclear power plant.
No damage from the quake, measured at magnitude 7.4 by the Japan Meteorological Agency, was detected at the Fukushima Daiichi plant and workers had been evacuated without reports of any injuries, operator Tokyo Electric Power Co (TEPCO) said. TEPCO said it was continuing to inject nitrogen into reactor No.1 after no irregularities were reported.
Engineers, who sealed a leak this week that had allowed highly radioactive water into the sea, are pumping nitrogen into one reactor to prevent the risk of a hydrogen gas explosion, and want to start the process in another two reactors.
There were no abnormalities in radiation levels around Tohoku Electric's Onagawa nuclear power plant, where fuel rods are being cooled with just one outside power source, Japan's nuclear safety agency said.
There were no immediate reports of injuries or damage elsewhere but people in areas covered by the tsunami warning should evacuate to higher ground, Japan's NHK public television said.
Large parts of northern Japan were without electricity according to local media early on Friday.
Japan is struggling to bring the Fukushima Daiichi plant under control after the March 11 magnitude 9.0 quake and tsunami that followed, which killed or left missing, about 28,000 people.