A strong earthquake jolted northeastern Japan on Sunday, triggering an evacuation at the crippled Fukushima nuclear power plant but there was no sign of further damage at the facility or reports of casualties along the coast. The Japan Meteorological Agency issued, and then lifted, a tsunami alert after the 7.1 magnitude quake which hit the same area that was devastated by a massive quake and tsunami on March 11. Officials said a 10 cm wave had been recorded. "The shaking lasted rather long and became gradually stronger," an official at Iwaki City, Fukushima told national broadcaster NHK. "I saw a book shelf shaking but nothing fell off. We are advising people not to go near the coast." At least 21,000 people were killed or went missing during the March disaster, which also cut power to the Fukushima nuclear plant and triggered a radiation crisis. There were no reports of injuries or damage from the quake so far, national broadcaster NHK said. The meteorological agency said the earthquake had occurred at a depth of 10 km (6 miles) off the northeastern coast just before 10 am local time. Tokyo Electric Power said workers at Fukushima had been evacuated to higher ground, adding that there was no immediate signs of further damage at the facility where workers have been struggling to build a cooling system to stabilize the reactors. The company said that despite the evacuations, water was still being pumped into the reactors to cool them, and nitrogen was also still being injected in two of the reactors, a safeguard meant to prevent further hydrogen explosions. The US Geological Survey initially estimated the quake's magnitude of 7.3, but then revised that estimate down to a 7.0 magnitude. The March 11 earthquake that struck off the coast of northeastern Japan had a magnitude of 9.0 and caused a tsunami that caused extensive damage along the coast and measured about 14 meters at the Fukushima nuclear plant. Japan's government has come under fire for its handling of the disaster, putting pressure on unpopular Prime Minister Naoto Kan to resign.