A magnitude-3.9 earthquake rattled the Lake Elsinore area Thursday morning, according to the U.S. Geological Survey.
The quake occurred at 9:39 a.m. with a depth of about 5.4 miles.
A 3.0-magnitude aftershock was also reported about a minute after the initial quake, according to the USGS.
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According to the USGS, shaking was reported in Whittier, Pasadena, Riverside, Menifee, Irvine, La Verne, San Dimas and Lake Forest.
There are no immediate reports of any damage or injuries.
How to stay prepared for earthquakes
While it is still nearly impossible to predict earthquakes, Californians can potentially learn about tremors a few seconds before they strike by signing up for an alert message.
- Government Emergency Alerts: Free text messages will be sent out when an earthquake with magnitude-5.0 or higher strikes.
- MyShake App: The free smartphone app for iPhone and Android users will send audio and visual warnings for tremblors with magnitude-4.5 or higher.
- Android Earthquake Alerts: Android users with updated operating systems are automatically subscribed to Android Earthquake Alerts.
How to protect yourself during earthquake
- Drop to the ground, cover your head until shaking stops.
- Do not stand in a doorway.
- Stay away from glass windows and mirrors.
- If you can't get onto the ground, cover your head with arms as much as possible and remain in place.