HARRISON COUNTY, Iowa — Three adults and three minors were injured after an initial crash led to a multi-vehicle crash in Harrison County Saturday afternoon.

According to the Iowa State Patrol, the accident happened around 4:11 p.m. on Saturday close to mile marker 80 on Interstate 29 northbound, west of Missouri Valley.

ISP says vehicles were slowing to merge to the fast lane after a previous accident in the east ditch impacted the roadway. One vehicle slowed to a near stop and was rear-ended by a second vehicle, which pushed that vehicle into a third car, pushing into two more cars, finally resulting in a sixth car going airborne and landing upside down in the median.

Six people received varying injuries during the crashes. 22-year-old Jens Marttinen was taken to the hospital by EMS air. 64-year-old Laurie Stee and 50-year-old Chad Cantrall were taken to the hospital via ambulance. A one and a nine-year-old were airlifted to the hospital, while a 16-year-old was transported via ambulance.

The crash brought traffic between Missouri Valley and Modale Exits to a standstill in both directions for just under four hours. Harrison County Sheriff’s Office, Missouri Valley Fire Department, Mondamin Fire and Rescue, Logan Fire and Rescue Association, and Harrison County EMA/Dispatch assisted ISP at the scene.

Iowa State Patrol says the crash is under investigation.