The occupant of a residence is unaccounted for, while another was sent to hospital following a fire north of Alliston.
Police said the fire broke out at 6:20 a.m. on 3rd Line in Essa Township.
Nottawasaga OPP responded and officers found the residence fully engulfed in flames.
Several emergency services attended the scene, including the Essa Township Fire Department and the Simcoe County Paramedic Services.
One adult was subsequently transported to a Toronto-area trauma centre and treated for injuries, police said in a news release.
Police said they have reason to believe a second adult was unable to exit the residence and is currently unaccounted for.
The Nottawasaga OPP Crime Unit and OPP Forensic Identification Services are investigating, under the direction of the OPP Criminal Investigation Branch, in conjunction with the Office of the Fire Marshall.
There is no known threat to public safety, but police are asking that you to avoid the area.
Anyone with information regarding the cause of the fire is asked to contact the Nottawasaga OPP at 1-888-310-1122 or Crime Stoppers at 1-800-222-TIPS (8477).
