A waste truck leaked poultry fat along 20 miles of roadway Tuesday, causing at least four crashes and making a stinky mess.

Virginia State Police said a truck hauling a waste product of poultry grease from a Perdue Farms plant left a valve open, and the fat leaked onto U.S. Route 13 from the plant to the Maryland state line.

At least four crashes and several spinouts were reported Tuesday morning on northbound Route 13, Sgt. Joe Bunting. One injured person was taken to a hospital, he said.

Bunting described the consistency of the grease on the road as a "glassy film" and said crews were sanding the road surface to help drivers get traction.

However, the gunk was sticking to the tires and spreading onto secondary roads in the region. He added that the grease caused a "really funky" odor.

The truck's driver was stopped at a weigh-in station near the Virginia-Maryland state line, Bunting said.

Perdue was sending a team to help with clean-up, Bunting said.

Julie DeYoung, a spokeswoman for Perdue Farms, said company officials were investigating the incident to determine how the spill happened. They believe the leak began sometime after the truck — which was driven by an independent driver — left the Accomac rendering plant.

DeYoung described the substance as poultry fat that is a byproduct of the rendering process.