According to the U.S. Geological Survey, a 6.6 magnitude quake occurred close to Honchō Monday morning.
The tremor struck the area at 21:52 UTC (07:52 local time). It occurred at a depth of 19 km with the epicenter located about 129 km south of Honchō. Seismologists first reported it as a 6.7 event, but later downgraded it to 6.6.
Did you feel it?
If you noticed the earthquake, you can submit a report via the USGS Felt Report form. So far, the agency has collected 4 online responses from individuals saying that they experienced the quake.

Impact and estimated losses
Green alert for shaking-related fatalities and economic losses. There is a low likelihood of casualties and damage. Recent earthquakes in this area have caused secondary hazards such as landslides and fires that might have contributed to losses.
Structure information summary
Overall, the population in this region resides in structures that are resistant to earthquake shaking, though vulnerable structures exist. The predominant vulnerable building types are heavy wood frame and reinforced/confined masonry construction.
Source: The U.S. Geological Survey