Saskatoon fire crews put out a grass fire west of the city Tuesday.The fire department was called around 7:45 p.m. with reports of a grass fire close to Highway 7.Crews arrived to find two blazes burning close to some train tracks.Fire department officals had a freight train stopped as it was approaching the scene in order to keep firefighters safe.The blaze was put out just over two hours later, at which point the train was allowed to pass through.No injuries were reported. A fire department news release stated the cause of the fire was undetermined.