CHICAGO – A 56-year-old woman was arrested at the Sears Tower on Thursday after authorities found a loaded handgun in her purse.

Authorities say Stephanie Warren, of Memphis, Tenn., didn’t realize she couldn’t carry the gun in Illinois.

Warren was charged with one count each of unlawful use of a weapon, failure to register a firearm in the state of Illinois and not having an Illinois firearm owner’s identification card, according to Chicago police spokesman Tom Polick.

Sears Tower building security stopped Warren after she went through a metal detector with a loaded .38 caliber revolver in her purse Thursday morning, police said.

Warren had a state permit for the firearm from Tennessee, which allows residents to carry a handgun if they have the permit, police spokeswoman Monique Bond told the Chicago Tribune.

“It didn’t dawn on her that our state did not have the same gun laws as hers did,” Bond said.

No one was harmed and service to the Sears Tower’s public viewing deck was not interrupted, police said.

“There was never any danger to the occupants,” Bond said.