California Earthquake: Officials Warn Of Aftershocks After 5.6 Magnitude Quake Rocks Northern Coast

The Humboldt County Sheriff's Department and Eureka Police Department sent officials to check on residents, but dispatchers said there were no immediate reports of emergencies. Things also seemed fine on the Hoopa reservation, according to Byron Nelson Jr., the tribe's vice chairman.

"It was just a mild shaking. It wasn't a sharp jerk," Sgt. Gene McManus of the Del Norte County Sheriff's Department, a neighboring agency, told the AP.

Debbie Bailey owns in office supply shop about five miles from the earthquake's epicenter. She says only a few items fell off the shelves, and the "jolt" of the quake itself lasted only a few seconds.

"[The earthquake was] like a pick-up-and-move, like a soft wave," she told the AP. "It didn't jar you, it was a gradual back and forth."

Other residents were more shaken by the quake.

At Pearson's Grocery Store in Weitchpec, Karen Pearson watched cans fall off the shelves as a man yelled for people to evacuate the store.

"It was very scary because you have no control of these things," said Pearson. "Hopefully it's over."

USGS Issues Aftershock Warning

Unfortunately for North California, the USGS is now telling residents to prepare themselves for possible aftershocks.