An undersea earthquake struck off the  Santa Monica area and rocked some people in Los Angeles awake early Monday morning.

According to the U.S. Geological Survey (USGS), there were a total of three earthquakes that hit the Santa Monica area today. The first and strongest was a 3.6-magnitude earthquake that hit at 2:17:11 AM PDT. The second was a 1.8-magnitude earthquake that hit at 04:11:29 AM PDT, closely followed by a 2.1-magnitude earthquake that hit at 04:51:39 AM.

All three earthquakes were centered roughly 20 miles from the Los Angeles Civic Center.

A Santa Monica police spokesman said he felt a “very brief and mild jolt,” but had not received any calls from the public.