'Megaquake' Risk Rises After 7.5 Japan Quake

A powerful 7.5 magnitude earthquake struck off northern Japan late Monday, injuring 23 people and triggering a tsunami in Pacific coast communities, officials said. Authorities warned of possible aftershocks and an increased risk of a megaquake.

• The Japanese government was still assessing damages from the tsunami and late-evening quake, which struck at about 11:15pm in the Pacific Ocean, around 50 miles off the coast of Aomori, the northernmost prefecture of Japan's main Honshu island, the AP reports. "I've never experienced such a big shaking," convenience store owner Nobuo Yamada told the public broadcaster NHK in the Aomori prefecture town of Hachinohe.

• A tsunami of up to 2.3 feet was measured in Kuji port in Iwate prefecture, just south of Aomori, and tsunami levels of up to 1.6 feet struck other coastal communities in the region, the Japan Meteorological Agency said.
• The Fire and Disaster Management Agency said 23 people were injured, including one seriously. Most of them were hit by falling objects, NHK reported, adding that several people were injured in a hotel in Hachinohe and a man in Tohoku was slightly hurt when his car fell into a hole.
• The meteorological agency reported the quake's magnitude as 7.5, down from its earlier estimate of 7.6. It issued an alert for potential tsunami surges of up to 10 feet in some areas and later downgraded to an advisory.
• Chief Cabinet Secretary Minoru Kihara urged residents to go to higher ground or seek shelter until advisories were lifted. He said that about 800 homes were without electricity, and that the Shinkansen bullet trains and some local lines were suspended in parts of the region. Nuclear power plants in the region were conducting safety checks, Kihara said.

• The meteorological agency issued a caution about possible aftershocks in the coming days. It said there is a slight increase in risk of a magnitude 8-level quake and possible tsunami occurring along Japan's northeastern coast from Chiba, just east of Tokyo, to Hokkaido. The agency urged residents in 182 municipalities in the area to monitor their emergency preparedness in the coming week.
• The quake struck just north of the Japanese coast that suffered the magnitude 9.0 quake and tsunami in 2011 that killed nearly 20,000 people and destroyed the Fukushima Daiichi nuclear power plant.
• "You need to prepare, assuming that a disaster like that could happen again," the meteorological agency's earthquake and volcano division official Satoshi Harada said. At 6:20am Tuesday, authorities lifted all tsunami advisories for the Pacific coastline in northern Japan, NHK said.