Update 2: Everyone has been cleared to return to the buildings. Facebook spokesperson Genevieve Grdina issued this statement: “Late this afternoon, we received a bomb threat and took swift action to evacuate several buildings at our Menlo Park campus. We take the safety and security of our people at Facebook extremely seriously and are glad that everyone is safe. We are working closely with local authorities to investigate this threat and further monitor the situation.”

Update: Facebook has confirmed that it is looking into a bomb threat on its Menlo Park campus. A few buildings, but not all, were evacuated, and everyone is safe.
A building in Facebook’s Menlo Park campus was evacuated after a bomb threat early Tuesday evening. Around 5PM, the Menlo Park police department warned people to avoid the area around the 200 block of Jefferson Drive as they investigated a bomb threat. Then they said 200 Jefferson Drive, the address of Facebook Building 24 and Instagram’s headquarters, has been evacuated and a bomb unit is on the scene.