The earthquake struck 1.25 miles east-southeast of Berkeley, Calif., with shaking felt as far away as Salinas, about 100 miles to the south, and Chico, about 150 miles to the north.

An earthquake with a magnitude of 4.3 rocked the San Francisco Bay Area early Monday, waking up many people, with more 24,000 saying they felt it, according to the United States Geological Survey.

"Trains are running at reduced speeds while we complete safety track inspections. Please expect residual delays of up to 20 minutes systemwide."