The Bow tower in downtown Calgary was evacuated Tuesday after police were called to the building to investigate reports of a man yelling threats inside.
They were called by security to search each floor of the 58-storey building — the tallest in Western Canada.
Police say each floor takes 15 minutes to search, so SWAT and canine teams were on site for hours.
The fire department was also on site.
Police had been advising motorists to avoid the area around the tower located on Sixth Avenue between Centre and First streets S.E.