Magnitude 5.9 earthquake strikes southern Ibaraki, injures dozens across Kanto including Tokyo

A magnitude 5.9 earthquake struck southern Ibaraki Prefecture at about 2 a.m. on Sunday, shaking eastern Japan including Tokyo and injuring at least 37 people.

The Japan Meteorological Agency placed the epicentre at a depth of 68 kilometres. Maximum intensity reached lower 5 on the Japanese scale in 17 municipalities across Ibaraki, Saitama, Chiba and Tokyo’s Adachi Ward.

The Fire and Disaster Management Agency reported 15 injuries in Tokyo and 22 in the surrounding prefectures. Most were light. One person was seriously hurt in Kanagawa.

No tsunami warning was issued. Shinkansen services continued normally, though some local and airport express trains faced delays. A partial ceiling collapse occurred at Ushiku City Hall in Ibaraki. Elevators trapped some people briefly in Tokyo.

The agency warned that areas with strong shaking should prepare for possible aftershocks of similar intensity for about a week, especially in the next two to three days. Past cases show a 10 to 20 percent chance of another quake of similar size.

Prime Minister Sanae Takaichi said the government set up a task force to assess damage. The quake was the strongest intensity recorded in Tokyo’s 23 wards in about five years.

The mechanism was a reverse fault under east-west pressure at the boundary of the Pacific and Philippine Sea plates. Long-period ground motion of class 2 was observed in parts of Saitama, Chiba and Tokyo.

Residents in the Kanto region reported the shaking lasting up to a minute. Early warning alerts sounded on mobile phones moments before the strongest motion arrived.