In pitch darkness on a gravel road in rural north central Mercer County, two young men were killed early Sunday when they collided head-on while driving similar dirt bikes — neither one equipped with lights, authorities said.

The riders — Garrett J. Arnold, 22, of Greenville, and Gage C. Shook, 22, of Hadley — reportedly were best friends.

Two days earlier on the same road, state police said, another young man died when he crashed his car.

Mercer County Deputy Coroner Robert Snyder pronounced Arnold and Shook dead at the scene of the wreck around 1:40 a.m. Sunday on County Line Road just west of Methodist Road in Salem Township.

Arnold was riding a 2003 Honda CRF450, and Shook was riding a 2003 Honda CRF20. They had been at a friend's house just before the crash, Snyder said.

Both apparently were headed east when they left the home. But at some point, Shook possibly experienced trouble with his bike.

“(Arnold) turned around to find out where his friend was,” Snyder said. They collided as Arnold was traveling west and Shook was eastbound.

Investigators believe the collision occurred at or near the center of the gravel road.

Snyder noted that both bikes did not have lights, and that stretch of the road has no streetlights and there are no houses in the immediate vicinity.

“I don't know how much visibility they had,” he said. Road conditions were not believed to be a factor.

Arnold was thrown north, and Shook was thrown backward. Their bodies landed on the road. Neither man was wearing a helmet or other protective gear.

Snyder pronounced both men dead of blunt force trauma to the head. Autopsies were not performed, and investigators are awaiting results of standard toxicology tests.

Authorities said that a 20-year-old Greenville man, who had been with Arnold and Shook at the friend's house, wrecked as he drove upon the double-fatal crash. He too was traveling east on a dirt bike without lights and without a helmet.

Police did not immediately release the man's name. He apparently suffered a broken leg and was taken to Meadville Medical Center, Snyder said. He later was transferred to UPMC Hamot.

On the same road in northeast Mercer County, a little east of Sandy Lake Road in French Creek Township, state police said, a 21-year-old Crawford County man was killed around 3:10 a.m. Friday when he lost control of his speeding car and struck a tree.

The driver, Justin Ryan Opatrny, was pronounced dead at the scene. Police did not release any other information.