Bob Leek, a district chief of emergency planning, died at the scene, said David Sheen, Toronto fire services division chief. The cause of death was not immediately known.
"It's hard," Sheen said, his voice cracking. "I'm sure all of our guys are having a rough time with it."
Ontario Minister of Community Safety Rick Bartolucci said the fire continued to burn Sunday evening, but was under control. The cause was under investigation.
The explosions also shut down Canada's busiest highway and a part of the subway system, snarling traffic for thousands of travelers.
Some residents said the blast was so forceful they felt their homes rock as though they had been struck by an earthquake. "It was just a tremendous explosion and blew all the windows out of the house, just blew the house up, and I just managed to get out of there in time," said Robert Helman, who was covered in cuts and bruises as he fled his home.
Fearing the air had turned toxic, police used bullhorns to order the estimated 12,500 residents within a mile radius of the plant to flee their homes immediately. Air quality tests later in the day showed the fumes were not toxic.
About a dozen terrified residents - some clad in pajamas and housecoats - found their way on foot to nearby Yorkdale shopping mall, where security offered them water and a place to rest.
Toronto fire services division commander Bob O'Hallarn saw at least five heavily damaged homes and said windows were blown out a fair distance from the scene. He also saw large pieces of metal on the street and said it looked like they were from tanker trucks.
Some residents were allowed to return home Sunday night. In cases where homes were found to be uninhabitable, residents were escorted back to shelters.
Many angry residents were demanding to know why such a facility was ever allowed in their established residential neighborhood. Josei Miceli, 59, who has lived there for 40 years, said the area is full of elderly people who aren't mobile.
"We weren't even advised that they were going to be there," said Miceli, who fled her home carrying her small Yorkshire terrier. "They just moved in and we've been concerned since they were there that something like this would happen."
Mayor David Miller said authorities are reviewing why the propane facility was allowed to be built near a residential area.
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