6.4-Magnitude Earthquake Shakes Northern California, Leaving Tens of Thousands without Power

A magnitude 6.4 earthquake jolted the extreme northern coast of California before dawn on Tuesday, injuring at least two people, damaging roads, bridges and power lines and leaving tens of thousands of homes and businesses without electricity.

The tremor, which struck at 2:30 am PST and was followed by more than three dozen aftershocks, was centered 215 miles (350 km) north of San Francisco offshore of Humboldt County, a largely rural area known for its redwood forests, local seafood, lumber industry and dairy farms.

The region also is known for relatively frequent seismic activity, although the latest quake appeared to cause more disruption than others in recent years.

Tuesday's temblor set off one structure fire, which was quickly extinguished, and caused two other buildings to collapse, according to the California Department of Forestry and Fire Protection (CalFire).

The department said its dispatchers fielded 70 emergency calls after the quake, including one report of a person left trapped who needed rescuing, spokesperson Tran Beyea said.

The county sheriff's office reported two people injured near the quake's epicenter, where damage to homes and roads was widespread. One of those victims was a child with a head injury and the other an older person with a broken hip, according to local media reports citing the sheriff's office.

There were no immediate official reports of fatalities.

The highway patrol reported at least four other roads in Humboldt County closed due to earthquake damage, and a possible gas line rupture under investigation. One section of roadway was reportedly sinking, the agency said.