David Gamero, 45 was at the hospital for an appointment, Henrico Police spokesperson Lt. Greg Dillard said.
Witnesses said they saw the man leave the building, return to his car, and retrieve the firearm.
One witness sensed something suspicious and called police.
Police responded - en masse - to search hospital grounds.
"We quickly locked the medical office building one down allowing no one to come in or out of the building," Dillard said.
"Henrico Police conducted a full inspection of the medical building before declaring it safe. The incident did not affect patient care and according to police, at no time was anyone in danger. The facility’s normal activities resume," hospital spokeswoman Malorie Burkett said.
During the lockdown, people in the hospital were told to stay inside and away from windows.
Police found Gamara and arrested him for not having a valid concealed weapons' permit.
Witnesses saw him being taken away in handcuffs.
No shots were ever fired in this incident.
"The subject was found to have concealed firearm on his person without a concealed weapons permit. The subject was arrested and charged with possession of a firearm without a concealed weapons permit. The investigation determined that the subject posed no threat to the occupants of the building," a Henrico Police spokesman said.
Police are still unsure why he brought a weapon onto the campus.
"Henrico Doctors’ Hospitals all have a no weapons policy on their campuses with the exception of law enforcement," Burkett said.
As a result of Tuesday's incident, HCA said they plan to add additional signage about the policy.
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