WACO, Texas (AP) -

A collision involving two tractor-trailers on Interstate 35 south of Waco forced the closure of northbound lanes and a traffic backup extending more than 10 miles.

Texas Department of Public Safety Trooper D.L. Wilson said it's not immediately clear what caused the vehicles to collide Tuesday morning in McLennan County but one caught fire and was destroyed. He says there were no injuries.

The collision happened in a construction zone that's become a signature of travel along the I-35 corridor south of Waco.

Texas Department of Transportation spokeswoman Jodi Wheatley said northbound traffic began moving again later Tuesday morning but the backup extended 10 to 12 miles.