A daring German trucker is being hailed as a hero after leaping aboard a moving tractor-trailer whose driver died at the wheel and bringing it to a stop before anyone was injured.

Cologne police say truckers spotted the 40-ton vehicle scraping along the center concrete barrier of the northbound A1 Autobahn on Wednesday night.

Police said Thursday that while other trucks blocked traffic the 43-year-old got out of his own vehicle and ran alongside the slow-moving tractor-trailer.

With the help of a police van that pulled alongside, he was able to vault from its fender onto the truck, smash a window with a hammer, open the cabin and take control of the vehicle, bringing it to a safe stop.

Rescue crews couldn't resuscitate the vehicle's 54-year-old driver.