Four firefighters were injured by a blast while they were fighting a warehouse blaze in Mississauga in the early morning on April 23.
Firefighters were unaware the warehouse they were entering contained explosive materials, deputy fire chief Greg Laing told press later on Wednesday morning.
A group of firefighters rushed into the building on Thamesgate Drive, just north of Pearson Airport, which was emitting smoke and then an explosion rocked the building, Laing said.
One firefighter was taken to hospital in critical condition but has since been downgraded to serious condition, Laing said.
Two others were taken to hospital in stable condition and the fourth was treated for smoke inhalation.
Firefighters were alerted to the fire around 4:30 a.m. on Wednesday and rushed to the scene.
“The fact that no one was killed was miraculous,” Laing said. “It looks like the scene of an IED explosion.”
Laing said that the wall of the building shielded the firefighters from the brunt of the blast, but their injuries are still “quite significant.”
The fire has since been put out. Its cause remains unknown.