Thornhill resident Evelyn Bumatay Castillo, 43, died in hospital on Saturday. Autopsy results found she died as a result of foul play.
Emergency responders found Castillo in a room at the Quality Inn at 50 Britannia Road East in Mississauga, where they were responding to reports of a fire.
Police said the fire happened in a single room at the inn.
The death is Peel region's fifth homicide this year. The regional police homicide and missing persons bureau is leading the investigation.