SAN DIEGO – A string of earthquakes struck Tuesday afternoon east of San Diego County, near Brawley, the U.S. Geological Survey reported.

A 3.6 preliminary magnitude earthquake was reported at 1:22 p.m., followed by a 3.7 preliminary magnitude quake just 8 minutes later at 1:30 p.m. Both quakes were reported a few miles outside the city of Brawley in Imperial County.

A 2.7 preliminary magnitude earthquake struck at 1:51 p.m. only a couple miles away from the first pair of quakes. Earlier in the day, a 2.8 magnitude earthquake was reported in the same area at 11:15 a.m.

The USGS Shake Alert system was activated by the 3.7-magnitude earthquake, which was initially reported as having a magnitude of 4.3, USGS said in a tweet.

While the other quakes were too small to trigger the USGS alert system to send out cell phone notifications, actions like opening firehouse doors could still have occurred, the agency said.

According to the USGS intensity map, shaking would not have been felt from the earthquake for most of San Diego.

There were no immediate reports of damages or injuries from the string of earthquakes.

Last week a 4.6 magnitude earthquake near Ensenada caused shaking to be felt throughout San Diego. A “non-earthquake event” also triggered the USGS Shake Alert System last Friday.