A 6.1 magnitude earthquake shook Japan's northern island of Hokkaido on February 25, according to the United States Geological Survey.
The tremors jolted Nemuro peninsula at a depth of 61 kilometres (38 miles), said the National Research Institute for Earth Science and Disaster Resilience (NIED).
Hokkaido, which is one of the main northern islands of Japan, was struck by a 5.1 magnitude earthquake a few days ago.
A seismologist on public broadcaster NHK warned residents to be vigilant against powerful tremors for about a week.
The authorities have not yet issued any tsunami warning.
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Notably, Japan falls in an earthquake-prone region, and people here are used to the tremors. The country sits on the Pacific "Ring of Fire," an arc of intense seismic activity that stretches through Southeast Asia and across the Pacific basin."