A 4.4-magnitude earthquake shook the Los Angeles area on Monday morning, jolting some people awake just before sunrise but bringing no immediate reports of serious damage.
The quake, centered about 6 miles north-northwest of Westwood and about 15 miles northwest of downtown Los Angeles, happened at 6:25 a.m., the U.S. Geological Survey said.
"I sort of sat up in bed, waited a second, then put my head down for a bit. I wasn't really afraid," a man walking his dog in downtown Los Angeles less than an hour after the quake told CNN affiliate KTLA. He didn't provide his name.
CNN's Alan Duke said he was half awake in his Hollywood Hills home when he felt a jolt that lasted a few seconds.
"It just served as a rude awakening," Duke said. "The sliding-glass doors were just rattling like somebody had slammed into them. Nothing fell off the walls."
The USGS's online ShakeMap showed that strong to moderate shaking would have been felt near the epicenter, with lighter vibrations felt in Los Angeles proper.
Geophysicist Paul Caruso said that significant damage or casualties generally wouldn't be expected with earthquakes weaker than a 5.5 magnitude, though results vary by region, often depending on construction codes and types of rock that exist underground.
At least six aftershocks followed the quake Monday morning, the strongest of which was a magnitude 2.7, said Egill Hauksson, a California Institute of Technology seismologist.