Residents in the San Francisco Bay Area were shaken awake in the early hours of Thursday morning after a magnitude-4.4 earthquake hit the region.
The quake's epicenter was on the eastern edge of Berkeley at a depth of eight miles, according to the United States Geological Survey, hitting just after 2:30 a.m. local time (5:30 a.m. ET).
It was initially reported by the USGS as a magnitude-4.7 event before being quickly downgraded.
NBC Bay Area Chief Meteorologist Jeff Ranieri said it lasted around 10 seconds.
There were no immediate reports of damage or injuries, but enough people tweeted they felt the tremor to make #earthquake the top trending topic worldwide.
Berkeley Mayor Jesse Arreguin said he would be monitoring for damage and told people to be wary of aftershocks.
Others reported that the earthquake set off alarms and knocked items from shelves.