Five cats died in a fire downtown, but a man’s life was saved when his little white dog woke him up in the middle of the night to alert him.

The four-alarm blaze, which started around 1 a.m. on Oxford Street in Kensington Market, spread to four row houses.

Toronto Fire said it may have started as a deck fire and is being investigated to determine if it is suspicious. More than 100 firefighters responded in 20 fire trucks and the main body of the fire was knocked down by 3 a.m., Captain Mike Strapko of Toronto Fire said.

“There still is concern there might be a structural collapse on the east wall there. The fact that the roof collapsed, it’s unstable inside," Strapko said. "Firefighters are still putting water on the roof area knocking down hot spots.”

Platoon Chief Kevin Shaw said one of the homeowners was alerted to the fire by his dog. He managed to escape unscathed along with his neighbours, a couple. However, some pets are believed to be missing. Two of the houses were vacant, Shaw said.

The estimated damage to the homes is around $1 million. Neighbours reported seeing “overwhelming black smoke” in the area and billowing flames from the roof of one of the houses.

Badly charred wood and leaning chimneys can be seen on the damaged houses. Strapko said the east wall may come down on its own and there is concern about the heavy load if the bricks come down.

This is the second fire in the area in a week. It’s cause is not yet known, but Division Cmdr. Andrew Kostiuk said the Fire Marshall and Toronto police will look at video surveillance to determine if there is a “firebug in the area.”

“We don’t know that for sure, but we are getting the same reports from our firefighters in the area about a number of small fires in the area,” Kostiuk said. “It seems suspicious.”

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