Officials reported that there were no injuries.
Tom Ahern, a police spokesman, said the man began shooting outside the Jesse Brown VA Medical Center Monday afternoon and tried to enter the lobby.
He said security officers apprehended the man near the hospital entrance. Police took the man into custody.
"Nobody was hurt, there was nobody injured, there was nobody hit," Jeffrey Sallet, special agent in charge of the FBI's Chicago field office, said, according to Fox 32. "We avoided tragedy here in the city of Chicago today."
Authorities recovered a rifle that the man is believed to have used.
Ahern said investigators haven’t determined what led to the gunfire or who the man might have been targeting.
The Associated Press contributed to this report.