Ontario Provincial Police say a second person has died following a fire late last week at an group home near the village of Oakwood, northeast of Toronto in Kawartha Lakes.
Police say one resident of the facility died in the fire and two other people were taken to hospital.
They say one of those people, who was an employee of the home, has since died of their injuries.
OPP say a young person remains in custody charged with two counts of second-degree murder and one count of arson causing bodily harm.
Accused will not be identified
They say the names, age, and gender of the victims and the accused will not be released.
Police say they were called on Friday after getting a report of a disturbance at the facility, and when officers arrived, they found the facility was on fire and called in local fire and ambulance crews.
City of Kawartha Lakes Mayor Andy Letham said in a statement he was "deeply saddened by the tragic fire that has taken place.''
The facility is operated by Connor Homes. A spokesperson said Sunday that the other residents have been relocated while the police investigation continues.
Bob Connor also said in an email that he did not immediately have any information about the extent of the fire damage.