Authorities have identified two members of an Amish family — a mother and young son — killed Sunday afternoon when a logging truck struck the back of their horse-drawn buggy in southern Venango County.

Mary Troyer, 31, and James Troyer, 10, both of the Clintonville area, died in the crash about 3:05 p.m. on Route 208 in Irwin Township, about two miles north of the Butler County line.

Venango County Coroner Christine Rugh pronounced the victims dead at the scene. Both died of multiple blunt force trauma, according to autopsies performed Monday, Rugh said.

Injured in the crash, investigators said, was Troyer's husband, Mahlon, 32, who was driving the buggy, and two other children of the couple, a boy and girl, whose names and ages were not released.

Mahlon Troyer and his daughter both suffered apparent serious injuries, and were flown by medical helicopter to St. Elizabeth Boardman Hospital in Youngstown, Ohio, and Children's Hospital in Pittsburgh, respectively.

Their conditions were not known. The injured boy was taken by ambulance to Grove City Medical Center, where he was treated and released.

State police said Richard R. Stanford, 54, of Punxsutawney, who was driving the truck, was traveling east on Route 208 and failed to see the slow-moving buggy in front of him. The eastbound buggy, police said, was straddling the white fog line when the tri-axle Peterbilt truck hit it.

Stanford, who was wearing a seat belt, was not injured. Authorities said he is “cooperating” with investigators.

Police said that the horse also was killed in the crash. The crash closed a portion of Route 208 for several hours.

Police and the Venango County District Attorney's Office continue to investigate the crash. District Attorney Shawn While declined comment Monday, saying the investigation was “too premature.”