A 5.6-magnitude tremor was registered in Humboldt County in northern California late Saturday, the US Geological Survey reported, adding that the estimated depth of the earthquake was 9.4 km (5.8 miles).
At the moment, there is no official information about damage or casualties in the region.
The news comes after earlier this month about 400 earthquakes of 4.0-magnitude or less rocked the southern part of the state in what scholars described as "swarms" of seismic activity.