OKLAHOMA CITY (AP) - A former Federal Railroad Administration official says early findings suggest human error led to a head-on collision between two Union Pacific trains in the Oklahoma Panhandle.

Gil Carmichael - now with the University of Denver's Intermodal Transportation Institute - said Tuesday the railroad has a solid reputation and that the tracks and signals were likely in good shape.

The Sunday morning crash killed two engineers and a conductor. Another conductor jumped from a moving train and survived.

The National Transportation Safety Board has said one of the trains was supposed to have moved to a side track to wait for the other to pass.

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