A series of earthquakes struck just south of the U.S.-Mexico border on Sunday and early Monday, with the largest reaching a magnitude of 4.9, according to the U.S. Geological Survey.
The first in a series of earthquakes occurred Sunday shortly before 10:30 a.m., centered about 20 miles southeast of Mexicali, near Delta, Mexico. That magnitude 3.3 earthquake was followed by three more, all weaker than the first, before the 4.9 earthquake struck at 11:22 a.m., according to the USGS.
During the next 15 hours, almost 30 more earthquakes would be recorded, all in the same area of Baja California. Most were below 4 on the moment magnitude scale, but at least three others measured above 4. The last one occurred Monday shortly after 2 a.m.
People reported feeling some weak or mild shaking throughout San Diego County, according to public filings shared with the USGS.
It was not immediately clear if the earthquakes caused damage or injuries.
In mid-February, another earthquake swarm hit roughly the same area, with more than 20 earthquakes recorded in a few hours around El Centro, California. No major damage was reported at that time.
