California has been shaken by a strong quake.
The 6.4 shake struck at 5:33am on Friday (NZ time) in the Mojave Desert's Searles Valley, about 160km north of Los Angeles at 8.7km deep, according to USGS.
It's the biggest to strike the southern Californian region since 1994. That quake measured 6.6 and killed dozens, the Los Angeles Times reports, but struck a heavily populated area in the San Fernando Valley.
"The epicentre is out in the desert area of southern California, but here in Los Angeles it was a very long-lasting, rolling-type feeling," US correspondent Sandy Hughes told Newshub. "Not a herky-jerky sort of earthquake like the Northridge earthquake back in 1994 - but I knew it had to be a pretty big seismic event for it to last that long and for us to feel it here."
She said it was alarming.
"You get lulled into a bit of complacency when you haven't had a big earthquake for a while. But we've had lots of smaller earthquakes - the scientists say that's a good thing, because if we have more of the smaller earthquakes it lets off the pressure, then you won't have a big, terrible and explosive earthquake."
Friday's quake was preceded by a 4.2 foreshock, and followed by aftershocks measuring 4 and 3.5.
Hughes said the foreshocks were felt in Los Angeles, but the aftershocks haven't been.
It's not yet known if there have been any deaths, injuries or significant damage.
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