The man held up a sign that read "call lawyer" during the lengthy standoff, which led to a mandatory evacuation. There were no reports of injuries, and there was no danger to the public, authorities ...

CBS News Chicago witnessed the man being tackled by law enforcement and removed from the courthouse lobby on a stretcher.

The Dirksen Federal Building in Chicago was locked down after reports of a knife-wielding person inside. FBI is investigating; locals urged to avoid the area.