A magnitude 3.1 earthquake rattled east Los Angeles County about 3:42 p.m., according to the U.S. Geological Survey. It was centered near Chino Hills on the L.A. and San Bernardino county line, about 5 miles east of Diamond Bar. It's the same area where a couple smaller quakes hit earlier Sunday. One was a magnitude 1.4 quake at 3:38 a.m., the other a magnitude 1.1 quake at 7:22 a.m. There have been no reports of injuries or damage.