CHICAGO —  Chicago police are investigating a burglary in an Uptown condo but the method the burglars used is a cause for concern for anyone living in an apartment or condo in the city.

Around noon on Tuesday, a mail carrier came to the door of the building in the 4700 block of N. Sheridan and took the key out of the silver lockbox, which gets postal workers into the lobby. He put the key back, delivered a package, and leaves.

Minutes later two teens or young men appear to open the lockbox.

One of the suspects is seen grabbing posted notices from FedEx and UPS, most likely in an effort to figure out which residents weren’t home.

The two suspects allegedly broke into a unit prying the door open. They spent a half hour inside and took $10,000 worth of valuables including credit cards, cameras and computers.

Also, the victim’s father was in the Chicago Fire Department.  “And he had his badge and they took that,” said condo association’s Thomas Olson.

The suspects are seen on video leaving with their backpacks and duffle bags stuffed.  One even grabbed a Diet Coke out of the fridge.

The condo building has changed the locks and reported the break-in to police

“If they can get into our lockbox that easily, whether it be with a key they stole or just something they found to easily open it, it’s essentially a way to get into any building that has that,” Olson said.

Police are investigating and the surveillance video should provide a big boost to detectives, as both of the suspects show their faces clearly on camera.