The USGS says the quake struck at about 7:43 p.m. and was centered almost 2 miles southwest from San Bernardino. The depth of the quake was listed at 9.63 miles.
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Earthquake expert Lucy Jones wrote on X that the location was "very close to the San Jacinto fault."
"That part of the fault is generally locked -- it had a M7 in the 19th century. We often see small quakes like this below locked segments," Jones' post said.
There were no immediate reports of significant damage or injuries.
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The quake was initially measured at a magnitude of 4.5 before it was downgraded to 4.2. The earthquake was reported as being felt as far north as the Antelope Valley, as far east as Indio and along the coast from the U.S-Mexico border to Malibu.
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This is the second magnitude 4.2 earthquake to strike in the San Bernardino area in 20 days. The first struck near Lytle Creek, a small remote community about 16 miles northwest of downtown San Bernardino, Jan. 5.
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City News Service contributed to this report.