MILWAUKEE -

Milwaukee police say a naked burglar tried to break into a veterinary clinic to steal drugs but got stuck in the air vents for almost 12 hours.

Police Lt. Mark Stanmeyer says employees of the Small Animal Hospital in Milwaukee came into work Monday morning and heard the muffled screams of someone calling for help. They discovered 19-year-old Shane Ray stuck in a narrow shaft.

The teen had crawled into the vent Sunday about 9 p.m., meaning he spent about half a day in the vent.

When police asked why he was naked, Ray said, "So I could slide through the duct." Stanmeyer says Ray suffered multiple cuts and scrapes from screws.

Milwaukee police say the air conditioner was severely damage as a result of this incident. HVAC repair workers said it would cost about $5,000 to fix.  The criminal complaint states Ray had cut a large hole into the duct pipe, where he left his clothing and cell phone.

Ray faces an attempted-burglary charge.