The accident occurred on September 30th, when a southbound CN freight train collided head on with a northbound CN freight train near Two Harbors, Minnesota. The trains were operating in non-signaled track territory. The northbound train had 118 empty iron ore railcars and had been given authority to operate on the single main track. The southbound train had 116 railcars loaded with iron ore and did not have authority to operate on the single main track. As a result of the collision, three locomotives and 14 railcars derailed.