An earthquake centered off the coast jolted Southern California on Saturday night, alarming residents as far as 70 miles inland, but there were no immediate reports of injury or damage, authorities said.

The tremor, registered 4.5 on the Richter scale and struck at 9:40 p.m. said Hall Daily, spokesman for the seismological laboratory at the California Institute of Technology in Pasadena.The epicenter was in the Pacific Ocean, about 10 miles southwest of Huntington Beach, an Orange County coastal community about 33 miles south of Los Angeles.