STEELE COUNTY, Minn. - The State Patrol is investigating a fiery crash involving two semi trucks and a car in southern Minnesota, but officials said nobody was hurt.

The crash temporarily closed the northbound lanes of Interstate 35 just south of Owatonna, shortly before 4:00 p.m. Thursday.

The State Patrol said a semi and a car were stopped in the right northbound lane due to traffic backups. Another semi crashed into the car, which then collided with the first semi. The trucks then started on fire, sending a plume of smoke into the sky that could be seen for miles.

Traffic was detoured onto other roads. Southbound I-35 was reduced to one lane.

One witness described a chaotic scene shortly after the crash. He said one man was walking on the interstate to warn approaching traffic.

"(He was) waving his arms getting everybody over to one side or the other. And no sooner he did that, an emergency vehicle, ambulance, came up the interstate right between all of us," said Rex Martindale.

Authorities said the drivers of all three vehicles, and a 7-year-old boy in one of the semi-trucks, suffered no injuries.

The northbound lanes of Interstate 35 reopened just before 10:00 p.m. Thursday.