Four motorcyclists, three men from Iowa and one man from Nebraska, were killed Monday, when they were hit by a pickup in a construction zone on Interstate 29, in western Iowa’s Harrison County.

Officials with the Iowa State Patrol say a pickup truck driven by a 21-year-old Nebraska man crossed the center line of a two-lane portion of Interstate 29 in a construction zone, and collided head on with the four motorcycles near Little Sioux.

Three of the motorcyclists died at the scene of the crash, which occurred just before 6 p.m. The fourth died after being flown to a hospital in Omaha.

Officials say only one of the cyclists was wearing a helmet. Each of the victims were believed to be in their 50s or early 60s. Authorities were withholding the victims’ identities until relatives could be notified. The pickup driver was treated for non-life threatening injuries at a local hospital.

Officials say the vehicle had been traveling north when it crossed the center line and into the path of the motorcycles, which had been traveling fairly close together. Investigators believe alcohol was a factor in the crash, which remains under investigation. The wreck shut down the roadway for hours in both directions.

By Ric Hanson, KJAN, Atlantic