A 12-year-old boy is still not accounted for after a Markham townhouse exploded and burned on Sunday, leaving three people injured.
York Regional Police said emergency crews were called to a residence on Bur Oak Avenue between Kennedy Road and William Berczy Road for a report of a building fire at around 11 a.m.
When fire crews arrived, smoke and flames were seen coming out of townhouse.
The fire was extinguished but the home sustained significant structural damage. Video from the scene showed damage to neighbouring homes as well.
Officers determined that a family of five lived in the home.
A 14-year-old boy and a six-year-old boy were rushed to the SickKids hospital. Their 41-year-old mother was also transported to a trauma centre with serious injuries. They all remain in critical condition.
A 12-year-old boy is still missing and is related to the other victims, a spokesperson with the Ontario Fire Marshal’s office (OFM) said Monday.
The father was not at the residence at the time of the fire and was later located.
Police said they expect to hold the scene for at least four days so crews can search the damaged building.
The Fire Marshal said crews are still working on getting into the basement, where they said they believe the missing boy is located.
The work will involve knocking down three adjacent units.
What caused the building to explode has not been determined, the OFM spokesperson said.
Investigators are asking anyone who may have seen or heard anything in the area to come forward.
Bur Oak Avenue between Kennedy Road and William Berczy Road remained closed Monday for the investigation.
Note: A previous version of this article stated the six-year-old child was a girl. The story has been edited to reflect new information from police that confirms the child is a boy.