An angry Chicago Police superintendent vowed Thursday to find out how a 14-year-old boy allegedly impersonated a police officer and even went on patrol for several hours last weekend.

"When we have a security breach, we put our officers at risk and we put the public at risk," Superintendent Jody Weis said at a news conference. "And that cannot happen again."

The boy pleaded not guilty Monday in juvenile court to impersonating an officer. He was discovered Saturday after he put on a uniform, walked into a South Side police station, received an assignment and spent five hours in a squad car with an actual officer.

The boy's ruse was discovered only after his patrol ended and officers noticed his uniform lacked a star that is part of the regulation uniform.

Weis promised a full investigation by the department and punishment for whomever was responsible for the "security breach." He also said he has asked the United States Secret Service to conduct its own probe of department procedures, and that the service has agreed to do so.

Weis said the department was lucky that the boy, who once took part in a program for youth interested in policing, apparently just wanted to be a police officer and "had no evil in his heart."

"He went about it the wrong way, but he was not here to hurt anybody," Weis said. "But what if it wasn't that person?"

Police have not identified the boy because of his age. Police have said the boy was not wearing a gun and did not issue any tickets.

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