A suspected thief who police say attempted to steal an idling car in Texas was likely unaware that someone was sitting inside the vehicle — and that person wasn't just an average joe.

"He was warming up the vehicle prior to leaving for work," Haltom City police spokesman Joe Hackfield said in a statement, according to KXAX-TV.

Inside the vehicle was a detective who was sitting in his car at about 5:15 a.m. when a black Mustang approached and dropped an individual off.

Image source: KXAS-TV

The suspected would-be car thief walked up to the vehicle and, unable to see through the frosted windows, opened the door, KXAS reported.

"So when he opens the door, I say, 'Police, show me your hands!'" the detective recounted to KXAS.

Image source: KXAS-TV

The suspect immediately took off running, but the detective wasn't about to let the alleged car thief's get away.

The officer called for backup and followed the Mustang until a patrol car located them. The driver led police on a six-mile chase, but was eventually taken into custody.

The man who was dropped off and opened the door, however, is still at large.

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