Authorities say a federal building in downtown Atlanta has been evacuated because of a suspicious package.

Atlanta police spokeswoman Officer Kim Jones said Monday that the U.S. Marshals Service evacuated the Richard B. Russell Federal Building and Courthouse because of a suspicious package on the side of the building. She referred questions to the Marshals Service.

A person who answered the phone at the Marshals Service said to call back later because they were in the middle of an evacuation.

People could be seen streaming out of the building and walking across a viaduct to wait about a block away. Police vehicles blocked traffic from accessing the streets around the building, and a variety of law enforcement vehicles gathered at one corner of the building.