Kitwanga is a small community in northern B.C. (Google Maps)

The Transportation Safety Board says a track failure contributed to the derailment of a freight train in northern British Columbia in January.

No one was hurt when 34 cars carrying wood pellets on the Canadian National Railway Co. train left the tracks between the communities of Smithers and Terrace.

The board's report on the incident says video and audio evidence from the train strongly suggests a sudden track failure occurred.

The report says testing on the same stretch of tracks in July and September 2019 showed the number of “deviations” in the width between the tracks had increased along that section.

The agency says the weight and number of railcars travelling on the route sped up the deterioration of the track before the derailment.

CN Rail says in a statement it is reviewing the board's report but has already increased and enhanced its automated track inspection program to detect and improve track conditions.