The Transportation Safety Board is investigating after a 1.5-kilometre-long freight train rolled away uncontrolled Tuesday at the Canadian Pacific Railway's main headquarters in southeast Calgary.
According to the TSB rail occurrence report, 80 freight cars rolled away slowly for approximately 750 feet (about 230 metres) at the Alyth yard.
It happened at about 3 p.m. on Tuesday.
No one was hurt, and the train remained on the track as it was brought under control after it rolled away.
The TSB said most of the freight cars on the 9,500-tonne train were loaded, but none was carrying dangerous or explosive goods at the time.
The safety of freight rail in Canadian communities re-emerged as a concern after a runaway train carrying crude oil smashed into downtown Lac-Mégantic, Que., killing 47 people and destroying half of the downtown core in 2013.
Calgary inner-city freight tracks have had several derailment incidents over the years. In 2016, there was a derailment in Alyth yard that was dubbed a human error issue. At the time, Coun. Gian-Carlo Carra said he gets one or two calls a month from CP about trains coming off the track.