More than 100 aftershocks occurred in the last 15 hours following a 7.2-magnitude quake at the U.S-Mexico border, it was announced on Monday.

Many of the aftershocks have occurred on the California side of the border just above the epicenter near Mexicali, Mexico, according to the California Institute of Technology (Caltech)

Dozens of the aftershock measure stronger than magnitude 4.0. Two in Ocotillo, Calif., which is near the border, measured 5.0, including the one that hit Monday at 6:33 a.m., Caltech scientist Kate Hutton said.

Residents in some areas in the region reported feeling the aftershocks. In Calexico, Calif. residents were jolted awake as a 3.1-magnitude earthquake struck at 4:12 a.m. Monday. "This is very typical for a 7.2 earthquake." said Hutton.

The 7.2-magnitude quake struck in Baja California, Mexico, southeast of Mexicali near the U.S.-Mexican border on Sunday, according to the U.S. Geological Survey.

The shaker rocked all of Southern California, and set high rise buildings in Los Angeles and San Diego rocking back and forth.

So far two persons were killed on the Mexican side.