Investigators are trying to determine what caused a fatal crash in a southeast Iowa farm field Wednesday. The crash happened along Highway 22, just west of Kalona, shortly after 3 p.m. The Iowa State Patrol reports 63-year-old Merle Miller of Kalona was driving a pickup, hitched to a cattle trailer, that left the road and drove several hundred yards through a field before hitting a tree. The vehicle then became engulfed in flames.

Miller was killed in the crash. Authorities say he may have suffered some sort of medical condition prior to the truck leaving the roadway.

Radio Iowa