A 4.0-magnitude earthquake strikes California. 3 smaller quakes strike minutes afterwards.

Image Credit: Zenrin Earthstar Geographics
According to USGS a 4.0-magnitude earthquake struck 17 miles northwest of Brawley, Imperial County, California minutes ago at a very shallow depth of 2.8km. Just 3km away there is the Saltes volcano.
The exact magnitude, epicenter, and depth of the earthquake might be revised in the next few hours as seismologists review their data. Based on preliminary data the earthquake should not have caused any significant damage.
Weak shaking expected to have been felt in the nearby towns or cities of Imperial Junction (pop. 1010) 8 miles away from the epicenter and also in the cities of Westmorland (pop. 2,300) 12 miles away, Brawley (pop. 25,900) 17 miles away, Imperial (pop. 17,100) 25 miles away, and El Centro (pop. 44,000) 29 miles away. In Calexico (pop. 40,100, 37 miles away), Coachella (pop. 44,600, 45 miles away), and Indio (pop. 87,500, 48 miles away).
UPDATE: Another 3 earthquakes struck Niland, California and 1 in Southern California minutes ago.