(CBS) – A Chicago towing company is in trouble for towing a vehicle that had people inside – in this case, two young children.

It happened on Sunday, around noon. A tow truck driver for Rendered Services Inc. spotted a car illegally parked in a handicapped spot on the Southwest Side. So, he towed the vehicle.

The problem: The driver didn’t notice the six- and nine-year-old children inside.

On the way to the Bridgeport towing yard, the frightened older child called his mother on a cell phone to report he was being “kidnapped.”  The mom called police, who went to the tow yard to make sure the children were okay; they were fine.

Why did the driver fail to notice the children? The windows had been treated with an especially dark tint. The driver told authorities he could not see them inside.

The car is registered to a Joliet man believed to be the kids’ father.

The towing company was cited for towing a car with people inside.