Two tractor trailers were involved in a collision that shut down a stretch of Highway 99 in McFarland, California.

The incident happened on Sunday morning, around 8:15 a.m., on the southbound lanes of Highway 99, just south of Pound Road.

The California Highway Patrol says one of the trucks “made an unsafe lane change” and struck the other. The impact caused both trucks to overturn, blocking all lanes in the southbound direction.

Both drivers suffered minor injuries in the incident. One of the drivers was transported to Delano Medical for treatment.

The southbound lanes were closed for approximately 4 hours, but have since reopened.

The names of the drivers have not been released. California Highway Patrol’s investigation remains underway.