A truck hauling hogs rolled over Wednesday on a highway ramp near Mankato, releasing at least 20 of the animals to roam where vehicles typically zoom along, authorities said.

The truck veered off the ramp shortly after 10 a.m. from westbound Hwy. 14 to southbound Hwy. 169 in North Mankato, according to the State Patrol.

The Minnesota Department of Transportation kept one lane of Hwy. 169 shut down near the crash site as responders rounded up the hogs. The ramp where the truck rolled over and another ramp nearby were closed.

"These hogs are going to cause a major problem," one of the first troopers on the scene was heard saying on emergency dispatch audio. "They are large, and they are all over. … We've probably got 20 to 30 hogs running everywhere."

The driver, Corey R. Ehlers, 30, of Winnebago, Minn., suffered minor injuries and did not require hospitalization, the patrol said.

Some of the hogs were killed in the crash, according to the company that owns them, Minnesota Pork Inc.