Tokyo Earthquake Magnitude 5.9 Rattles Eastern Japan and Injures Over 30

An early morning earthquake shook the Tokyo metropolitan area and surrounding prefectures on Sunday, August 23, prompting emergency mobile alerts and disrupting regional transportation networks. According to the Japan Meteorological Agency (JMA), the tremor struck at 2:00 a.m. local time with its epicenter located in the southern Ibaraki Prefecture at a depth of 68 to 70 kilometers (42 miles). Geological Survey recorded it at 5.8.

Injuries and Infrastructure Disruptions Across Five Prefectures

The shaking injured at least 37 people across five prefectures in the region, according to prefectural officials and the Fire and Disaster Management Agency. Fifteen injuries occurred in Tokyo, nine in Saitama, eight in Kanagawa, four in Chiba, and one in Ibaraki. Most of the injured were hurt when they fell down or hit themselves against furniture or doors as they were caught off guard by the quake while sleeping and got out of bed in a panic, officials said.

Among those injured was a woman in her 80s who fell off the bed and suffered a serious hip injury in Yokohama, in the Kanagawa prefecture, the Yomiuri newspaper reported. A 23-year-old man told the Asahi newspaper that he felt a vertical jolt seconds after his earthquake alert went off when he was shopping in Tokyo’s eastern district of Taito. He said he feared getting hit by merchandise that fell from shelves as the building shook.

Infrastructure felt the impact immediately. An underground water pipe ruptured in Tokyo’s eastern ward of Koto, with water pouring onto the road, NHK footage showed. The pipe has been repaired and the leak stopped. In Ibaraki Prefecture, part of the ceiling at the Ushiku city hall building partially collapsed. TEPCO Power Grid reported that about 460 homes in Tokyo had power outages. The quake also caused delays to express trains serving Tokyo and Narita Airport and other local trains serving northeastern regions, but Shinkansen bullet trains were running normally, their operator East Japan Railway Co. said.

Government Response and Nuclear Facility Status

The government set up a task force to assess the extent of possible damage, Prime Minister Sanae Takaichi said on X. Meanwhile, the Nuclear Regulation Authority reported there were no reports of anomalies from about a dozen nuclear power plants and other facilities that handle nuclear materials.

The JMA measured the earthquake’s intensity at a lower 5 on Japan’s Shindo scale, a level where most people may feel frightened, need to hold onto something to steady themselves, or experience items falling from high shelves. This intensity was detected in Adachi ward in Tokyo, as well as parts of Ibaraki, Saitama, and Chiba prefectures. Meanwhile, various areas in Tokyo, Tochigi, Gunma, and Kanagawa measured a Shindo intensity of 4. The shaking lasted as long as one minute in some areas and was felt widely from northeastern to central Japan.

Aftershock Warnings and Recent Seismic Activity

The Japan Meteorological Agency urged residents in the area to use caution against another possible moderate earthquake for about a week, noting that such risks are especially prominent during the first two to three days following the initial event, and asked people in areas that experienced heavy shaking to stay extra vigilant.

Last month, a magnitude 7.1 quake struck the Kumamoto area on Japan’s southernmost island of Kyushu, killing 38 people and injuring 364. That earlier disaster also destroyed more than 1,500 buildings and damaged nearly 20,000 others.