A 6.4-magnitude earthquake has struck in northern California, plunging more than half of the hardest-hit county into darkness.
The earthquake, which was reported at 2.34am local time on Tuesday, had a depth of 10 miles and was centred 7.5 miles southwest of Ferndale, Humboldt County – 130 miles north of San Francisco, according to the US Geological Survey (USGS).
The quake was then followed by at least two aftershocks of 4.6 magnitude and 3.1 magnitude.
No injuries have been reported so far and the United States’ National Oceanic and Atmospheric Administration (NOAA) has said that there is no current tsunami threat.
Power went out across more than half of Humboldt County as a result of the quake, with 52.7 percent of the area’s 99,000 customers in darkness at 3.10am, according to Poweroutage.us, which tracks utility service.
One woman posted on Twitter that power had gone out in the Ferndale area and that her home had been left “a mess” from the tremor.
“That was a big one. Power is now out in #ferndaleca. House is a mess. #earthquake,” she tweeted along with a video showing the destruction inside her home.
A resident in nearby Sacramento said that he was alerted to the earthquake by the USGS’s Shake Alert app and noticed the blinds in his home shaking.
“The @USGS_ShakeAlert app alarm went off, warning me to expect shaking here in Sacramento from #earthquake in Eureka. I didn’t feel it my blinds did,” he said.
California state Senator Mike McGuire tweeted that he was in contact with power company PG&E and emergency management, while the state is standing by to assist people in need.
“We’re in contact with Emergency Management officials in Humboldt along with PG&E,” he said.
“The #earthquake was significant…6.1-6.3 magnitude. Aftershocks continue. No tsunami threat at this time. The State stands ready to provide any and all assistance needed.”
The USGS activated its Shake Alert system for those living in affected areas.
“The quake was large enough to trigger the delivery of #ShakeAlert-powered alerts to cell phones by the @fema Wireless Emergency Alert System,” the agency tweeted.
“We hope everyone is safe and if you felt shaking or got an alert you took a protective action like Drop, Cover, and Hold On.”
The earthquake comes just three days after the San Francisco Bay Area was struck by a magnitude 3.6 earthquake.
That quake was felt early on Saturday morning in the East Bay area just northeast of El Cerrito, near Oakland.
California is susceptible to experiencing many earthquakes, in part due to the fact that the San Andreas Fault runs through the state.
The fault, a boundary between the Pacific Plate and the North American Plate which extends around 1,200km through California, is one of the most active fault zones in the world.
