A crash in Durham Sept. 21 that killed two men and severely injured two others was the result of human error when the driver of a pickup truck ran a stop sign and slammed into a dump truck, state police said.

Maine State Police investigators determined that a 2003 Chevrolet pickup carrying three men was traveling eastbound on Runaround Pond Road when the driver of the pickup failed to stop at the intersection with Route 9, also known as Hallowell Road.

The pickup, owned by Plowman Construction, was being driven by Brandon J. Harthorne, of Cornish. With him were Jeremy J. Reardon, 35, of Limington, and 21-year-old Malakai X. Cawood.

The dump truck, which was being driven by 42-year-old Clifton H. Larrabee, of Durham, was headed south on Route 9 when it was struck by the smaller truck.

The force of the impact caused the dump truck to spin 180 degrees and turn over onto its side; the pickup spun violently and burst into flames.

Harthorne, the pickup’s driver, was not wearing a seat belt and was thrown from the vehicle through the driver’s door. He was killed instantly by a blow to the head.

Reardon, who was in the front seat, also was not wearing a seat belt and suffered significant injuries in the crash. He was taken by LifeFlight helicopter to Central Maine Medical Center in Lewiston.

Cawood was seated in the rear passenger seat and also was not wearing a seat belt. He was ejected from the vehicle and also died instantly from a head injury.

The dump truck’s driver, Larrabee, was wearing a seat belt and was taken to Maine Medical Center in Portland with serious injuries.

State police found no indication that mechanical failure, road or climate conditions, speed or the presence of drugs or alcohol contributed to the crash.