See more of our coverage in your search results.

A 4.2-magnitude earthquake rattled Southern California early Sunday, striking 70 miles north of Los Angeles, according to the US Geological Survey.

The quake hit just after 3:30 a.m., with its epicenter located about 1 mile southeast of Frazier Park, a mountain community along the Interstate 5 corridor near the LA County line.

The agency’s ShakeAlert early warning system was activated following the temblor.

There were no immediate reports of injuries or damage.

Earthquakes of that size are frequently felt across Southern California, particularly in communities near major fault systems.

The earthquake comes less than three weeks after a magnitude 5.6 temblor struck near Redwood Valley in Mendocino County, knocking out power to thousands of Pacific Gas & Electric customers, triggering a series of aftershocks and causing minor injuries and damage.

That quake, centered about 115 miles northwest of Sacramento, also prompted Gov. Gavin Newsom’s office to monitor the situation, though officials reported no tsunami threat.

Sunday’s earthquake was significantly weaker, but a magnitude 4.2 temblor is still capable of producing noticeable shaking, rattling homes and businesses and causing minor damage near its epicenter, according to the U.S. Geological Survey.

The latest shaking also comes as scientists continue to warn that Southern California remains vulnerable to a much larger earthquake.

A study published last month found stress levels along two major segments of the San Andreas and San Jacinto fault systems have reached their highest levels in at least 1,000 years. Researchers said the findings do not mean a major earthquake is imminent, but they reinforce long-standing concerns that the region is primed for what many Californians refer to as “The Big One.”

“We have been lucky in California not to experience a large urban earthquake since 1994 on Northridge,” Ahmed Elbanna, director of the Statewide California Earthquake Center and a professor at the University of Southern California, said. “In order to release the stresses, the stress levels that we are talking about in this study, we need a magnitude 7 or larger earthquake.”

California’s top news, sports and entertainment delivered to your inbox every day.

“We have been lucky in California not to experience a large urban earthquake since 1994 on Northridge,” Ahmed Elbanna, director of the Statewide California Earthquake Center and a professor at the University of Southern California, said. “In order to release the stresses, the stress levels that we are talking about in this study, we need a magnitude 7 or larger earthquake.”

Please provide a valid email.

By clicking above you agree to the Terms of Use and Privacy Policy.

Never miss a story

According to researchers, a magnitude 7 or greater earthquake striking Southern California could affect nearly 24 million people across the Los Angeles metropolitan area and the Inland Empire.

Such a quake would be more than 125 times stronger than the magnitude 5.6 earthquake that struck Northern California in June.

California experiences thousands of earthquakes each year because it sits along the boundary between the Pacific and North American tectonic plates.

While most are too small to be felt, the state’s extensive network of faults — including the San Andreas, San Jacinto and Hayward faults — makes it one of the world’s most seismically active regions.