Resident Steve Anderson says the derailment happened just after 4 p.m. on Thursday, and the downtown was blocked off for a time.
He says fortunately, all the train's tanker cars are still on the track.
Slave Lake Mayor Tyler Warman says no injuries are reported.
There were actually two derailments Thursday on the Prairies — four cars carrying crude oil on a Canadian Pacific Railway came off the rails in Estevan, Sask., but there were no spills or leaks.
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