A swarm of earthquakes rattled Southern California in less than 24 hours, centered along the Mission Creek strand of the San Andreas Fault near Indio in the Coachella Valley. The sequence began Monday night with a magnitude 4.9 quake, followed by a 3.8 tremor and many smaller shocks.

According to the US Geological Survey, more than 150 seismic events were recorded. While most were too weak to feel, over a dozen caused noticeable shaking across populated areas, reaching as far as Los Angeles and San Diego.

So far, “No injuries or serious damage have been reported,” but officials caution that the activity may not be over. Scientists say “there is a high probability of additional quakes in the coming days,” as stress continues to shift along the fault.

Experts note that this swarm adds to long-standing concerns about the southern San Andreas Fault. Research shows this section has been storing stress for centuries, increasing the risk of a powerful release.

Studies estimate a strong chance of an earthquake above magnitude 6.7 striking California within the next two decades. While this recent activity caused little harm, it is a clear reminder that Southern California remains “one of the most seismically vulnerable regions in the world.”