An upgraded 4.1-magnitude earthquake shook the Ludlow area Monday in San Bernardino County, according to the U.S. Geological Survey.
The temblor came minutes after an upgraded 3.5-magnitude quake in the same area.
A third quake, a preliminary 2.8, was reported in the same area at 7:30 p.m.
Despite the series of quakes, not many residents reported feeling them.
About 13 people reported feeling the quake in San Bernardino County.