An alert sent to people across California warning about a strong earthquake striking Northern Nevada on Thursday morning was sent in error, officials said.

At 8:06 a.m., the U.S. Geological Survey sent out an alert about a magnitude 5.9 earthquake that struck near the state capitol in Carson City. Alerts were received by people as far away as the San Francisco Bay Area, nearly 200 miles away.

Several minutes later, the agency canceled the alert and an entry about the earthquake on the USGS website was deleted.

"There was no M5.9 earthquake near Carson City, NV," the agency said on social media.  

Meanwhile, a message on the USGS website read, "The event did not occur, and has been deleted from USGS websites and data feeds."

It was not immediately known why the alert was sent. The agency is investigating.