Deadly earthquake jolts northern California

A powerful 6.4-earthquake hits northern California, killing at least two people and cutting power to around 70,000 customers.

California is regularly shaken by tremors, and seismologists say a quake capable of causing destruction is almost certain to hit the state in the next 30 years.

California is regularly shaken by tremors, and seismologists say a quake capable of causing destruction is almost certain to hit the state in the next 30 years.

At least two people have died after a powerful earthquake struck off the coast of northern California, triggering rockslides and cutting power to tens of thousands.

The relatively shallow 6.4-magnitude quake hit overnight, 40 kilometres southwest of the port city of Eureka, in Humboldt County, the US Geological Survey (USGS) said on Tuesday.

County emergency officials said there was significant damage in the Eel River Valley community.

"Approximately 11 individuals have been reported as injured," the sheriff's office said.

"Additionally, two individuals have died as a result of medical emergencies occurring during and/or just following the earthquake."

The office gave no further information about the deaths.

Around 70,000 customers remained without power, with Pacific Gas and Electric Company not able to say when it will be restored.

"Damage assessments are currently underway, with significant structural damages, including gas and water lines, observed in the Rio Dell community and moderate damages to properties throughout the Eel River Valley," the sheriff's office said.

Aftershocks

A series of aftershocks were recorded in the wake of the quake, with the USGS predicting more over the coming days in the area, which is more than 400 kilometres northwest of San Francisco.

One roadway buckled, blocking access to the town of Fernbridge, tweeted Dania Romero, a reporter for KAEF television station.

Photos and videos posted to social media showed shattered windows, items in homes tossed from shelves and a supermarket aisle littered with spilt goods.

Debris and small rockslides were reported along a central route from Humboldt County to central California.

California is regularly shaken by tremors, and seismologists say a quake capable of causing widespread destruction is almost certain to hit the state in the next 30 years.

A 6.7-magnitude earthquake in 1994 in Northridge, northwest of Los Angeles, left at least 60 people dead and caused an estimated $10 billion in damage, while a 6.9 quake in San Francisco in 1989 claimed the lives of 67 people.

READ MORE: Offshore earthquake in California leaves thousands without power

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