Portions of westbound State Road 400 have reopened following a crash Sunday morning.
Troopers said the crash happened just before 8 a.m. in Polk County.
According to a news release, a tractor-trailer, truck tractor and a pickup truck were traveling west on State Road 400 near milepost 34.
The pickup truck stopped for traffic congestion and the truck tractor slowed down, but the tractor-trailer did not slow down or stop.
Florida Highway Patrol said the tractor-trailer rear-ended the truck tractor, which caused it to rear-end the pickup truck.
The 32-year-old driver of the tractor-trailer had serious injuries but the other drivers were not injured.