TOLEDO - A 9-year-old boy died Saturday when a dump truck driven by his dad rolled over on a rural logging road in Lewis County.

Deputies and medics who responded said the accident happened on the Weyerhaeuser 516 Road south of Toledo.

They said a 31-year-old Mossyrock man was driving a 1999 Kenworth dump truck south on the logging road with his son, who was in the passenger seat.

As the driver began heading downhill, the vehicle’s brakes failed to slow the vehicle enough to negotiate a sharp left turn in the road.

The truck left the roadway and rolled onto the passenger side, deputies said.

The boy died from massive head injuries and was pronounced dead at the scene.

"The 9-year-old had his seat belt on, and at this point we think it was just a tragic accident," said Lewis County Sheriff's Office Cmdr. Steve Aust.

The driver was airlifted to Southwest Medical Center in Vancouver with non-life-threatening injuries.

The investigation is continuing into the cause of the accident.

The name of the victim has not been released.