3.4-magnitude earthquake shakes San Bernardino, USGS says

SAN BERNARDINO, Calif. -- A preliminary-magnitude 3.4 earthquake shook the San Bernardino area on Thursday morning, according to the U.S. Geological Survey.

There were no immediate reports of injuries or damage.

The temblor struck at 5:44 a.m. and was centered 2 miles north of Colton, the USGS said.

DEVELOPING: More details will be added to this report as they become available.