The Illinois State Police is investigating a multiple fatality vehicle accident in Montgomery County. ISP District 18 Troopers responded to investigate a fatal crash on Illinois Route 185 near East 14th Road in the Coffeen area in Montgomery County. At 6:21 on Friday evening, a Toyota Sienna was traveling eastbound and a Ford F-150 was traveling westbound. The F-150 crossed into the oncoming lane and struck the Toyota head-on. All four occupants of the Toyota were pronounced deceased by the Montgomery County Coroner on the scene. The occupants of the Toyota Sienna were 72-year-old Jackolyn C. Protz of Sullivan, 73-year-old William H. Protz, of Sullivan, and two 14-year-old females from Vandalia. The driver of the F-150, a 17-year-old male from Harvel, suffered life-threatening injuries and was transported to a local trauma center by ARCH Helicopter. The ISP Traffic Crash Reconstruction Unit is continuing the investigation. No further information is available at this time. Stay tuned to Regional Radio News for more on this story as it becomes available.