Second, Larger Earthquake Rattles The Inland Empire

ONTARIO, CA — A magnitude 3.9 quake centered in Eastvale followed shortly after a 3.5 magnitude quake in Ontario on Saturday morning, according to the United States Geological Survey.

The second quake struck at 10:34 a.m. The two quakes struck within a short distance of one another.

The larger quake was initially reported as a magnitude 4.1 quake by the United States Geological Survey before being downgraded to a 3.9.

The agency said the first quake struck around 10 a.m. The epicenter was located about 5 kilometers southeast of Ontario, according to officials.

It's unclear if anyone suffered injuries in the quake.

The first quake proved to be a foreshock, and both quakes were followed by several smaller ones Saturday morning. The swarm of small quakes is not surprising, said Seismologist Lucy Jones.

"Today we are having a small swarm in the Fontana Seismicity Lineation, a northeast-striking line of many small quakes," she wrote on X. "Today we have so far M3.9, M3.5 and many M1s and M2s. I've seen this type of cluster in Fontana dozens of times in my decades watching SoCal quakes."

Did you feel it? Report it to the USGS for tracking purposes.

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