Strong quake shakes Hokkaido as authorities urge vigilance

A strong earthquake hit eastern areas of Hokkaido Prefecture in the early hours of Saturday, with authorities warning that more could be in store for Japan’s northernmost prefecture.

The temblor occurred around 1:40 a.m. at a depth of about 40 kilometers off the southeastern coast of the Nemuro Peninsula in Hokkaido, according to the Meteorological Agency. There was no threat of tsunami.

The quake, with an estimated magnitude of 5.8, measured a lower 5, the fifth-highest level on the Japanese seismic intensity scale, in the city of Nemuro. The agency called on people in areas jolted by the quake to remain alert for more temblors measuring up to a lower 5 for about a week.

Off the southeastern coast of Hokkaido, an ocean plate is subducting beneath a land plate, and Saturday’s quake occurred at the boundary of the two plates, according to the agency. An earthquake with an estimated magnitude of 5.1 struck nearby Wednesday, registering 4 on the Japanese scale in some areas of Hokkaido.