RCMP say 28-year-old Andrew Evans was wanted on several arrest warrants and numerous attempts to locate him led police to the house from where he fled.
Const. Dan Moskaluk says that while officers were speaking to an occupant on the main floor, Evans ran upstairs and jumped out the window but Mounties stationed outside were unable to stop him before he dove into the river.
Moskaluk says police called for the fire department's rescue boat and saw Evans swim back towards the shore, where he remained in the water while holding a tree branch and spoke to officers at the water's edge.
He says a Mountie urged Evans to get out of the cold, fast-moving water but the man ignored that advice and floated downstream toward a set of rapids where he disappeared from sight.
Moskaluk says Evans then resurfaced and appeared to be in distress before he was swept under again, at which point the rescue boat arrived and searched the river to the U.S. border but without success.