Police on Tuesday evacuated buildings on Facebook's headquarters in the Silicon Valley after an anonymous bomb threat was received.
The San Mateo bomb unit responded to the Tuesday afternoon threat at the company's campus in Menlo Park, California, the Menlo Park Police Department said in a statement. The bomb squad swept the targeted building with explosive-detecting dogs but turned up no suspicious packages or devices.
"The building is all clear and secure," Menlo Park police said in a statement.
A Facebook representative confirmed that a few buildings on the campus had been evacuated as a precaution and that all employees were safe.
"We are working closely with local authorities to investigate this threat and further monitor the situation," Facebook spokeswoman Genevieve Grdina said in a statement.
First published Dec. 11, 7:15 p.m. PT.
Update, 8:15 p.m.: Adds police statement that no device was found.