A driver was seriously injured and a horse was killed in a crash involving two semi-tractor trailers Wednesday morning in Polk City. 

The crash occurred around 4:45 a.m on Commonwealth Avenue just north of Green Pond Road. 

Authorities said one or both of the semis struck the horse, causing fatal injuries to the animal. 

One of the trailers overturned and the driver was pinned in the truck, authorities said. Rescue crews were able to extract the driver and he was transported to the hospital with serious injuries. 

The driver of the second semi was not injured in the crash. 

The road was shut down in both directions for several hours after the crash.