Five members of a Toronto family are in hospital after flames ripped through a Scarborough home early Tuesday morning.

Firefighters rescued three people who were trapped inside a burning house on Canlish Road, near Birchmount Road and Lawrence Avenue East, after flames erupted at about 1 a.m.

After the three were rescued, emergency personnel immediately began CPR on the front lawn, said Toronto Fire Services division commander Bob O’Halloran.

During the rescue, one of the victims was found in a bathroom with towels stuffed under the door in an attempt to escape the smoke, O'Halloran said.

All three were rushed to hospital in critical condition, and at least one was without vital signs, a Toronto EMS spokesperson told CP24.

One of the critically injured victims was taken to Toronto General Hospital for treatment in a hyperbaric oxygen chamber, O'Halloran said.

A family member told CP24 the seriously injured people are a grandmother, a grandfather and their son-in-law.

In addition to those victims, a woman suffered serious but non-life-threatening injuries and her 22-month-old child was reported to be in stable condition at SickKids.

Three generations of a family lived in the house, and it is believed one of the occupants is a pregnant woman.

O'Halloran said up to seven people lived in the house, and three or four managed to escape on their own before firefighters, paramedics and police arrived.

The fire set off the home's smoke detectors, O'Halloran said.

"Our crews heard them and I would expect that that’s one of the things that alerted the people and managed to get four of them out," O'Halloran said.

Fire may have started in cube van

When firefighters arrived, the house and a cube van parked in the driveway were in flames, said Toronto Fire Services spokesman Capt. Mike Strapko.

Investigators are looking into whether the fire started in the cube van before spreading to the family's house and a neighbouring home.

An investigator told CP24 reporter Cam Woolley the fire originated somewhere near the front of the van, which was partially underneath a carport.

At its peak, about 40 firefighters battled the blaze, which was brought under control by 1:35 a.m., Strapko said.

Witness Crystal Anderchek said she was on her way home when she noticed smoke in the sky.

When she arrived at the fire scene, no emergency personnel were there yet and a young man was holding the child in front of the home as the fire burned out of control.

Anderchek said she and another witness banged on doors to alert the occupants of the burning homes.

A short time later, she held the baby as people tried to help the occupants who were trapped in the house.

“The other guy was trying to break the windows to make sure there was nobody else (inside),” Anderchek said.

The Office of the Fire Marshal is investigating the cause of the fire.

With files from CP24 reporter Cam Woolley

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