Man dies after a runaway U-Haul truck barrels down San Francisco hill

San Francisco police are looking into a freak accident that killed a 66-year-old San Francisco man.

According to police, the man who died, John Deamicis, was in a runaway U-Haul moving truck that eventually crashed into a FedEx truck. 

Shortly after noon on Tuesday, the U-Haul truck began barreling down Jones Street. 

Investigators are still trying to piece together how the truck ran away in the first place, but they say the occupants of the truck were helping someone move, when the truck suddenly began rolling down the hill. 

One of the men somehow got out of the vehicle while it was moving, and was hit by a nearby parked car. 

"I don't know if the brake was disengaged or the exact circumstances, but the vehicle began rolling," said Lt. Mark Moreno. "A person got trapped between the U-Haul truck and a vehicle up there. That person was rushed to San Francisco General."

Police say the man who was hit later died from his injuries.

The U-Haul truck continued rolling about a half a block down the steep hill, barreling through a busy intersection. 

Police told KTVU that a man who was in the passenger seat as the truck began rolling away yanked on the steering wheel, and swerved the U-Haul into a parked FedEx truck.

Police say the man's quick action likely saved lives, since the truck would likely have continued rolling downhill in an area filled with pedestrians. 

"As the truck began rolling he was able to kind of steer it away from pedestrians, I don't know how many people were on the street at the time, but he was able to steer it away from pedestrians and other cars and into that truck," Moreno said. 

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Witnesses to the aftermath of the crash say the older man who was struck was the grandfather of the young man who managed to steer the U-Haul into the FedEx truck.

Street ambassadors and the passenger from the U-Haul administered CPR trying to save the older man's life. Police say emergency crews rushed the older man to the hospital, but investigators say he died from his injuries.

Police are investigating to see if there was some kind of mechanical failure or operator error that led to the runaway U-Haul.