Hamilton Fire

Hamilton Fire investigators are on scene Friday trying to determine the cause of a house fire that left three people dead Thursday. (CBC)

Fire investigators say that a mother and her two children killed early Thursday morning in a Hamilton house fire died from smoke inhalation.

Richard Derstroff, investigator with the Ontario Fire Marshal's office, says the fire started in the basement at their home in the area of Upper Ottawa Street and Limeridge Road.  

Investigators are on the scene Friday looking into the cause of the fire. 

One smoke alarm on the main floor has been recovered. 

Forensic engineers are on site Friday to examine and confirm whether or not it operated. 

Laird Drive fire

Firefighters on the scene of a fatal blaze in Hamilton. They were called to the scene just after midnight on Thursday. (Tony Smyth/CBC)

Neighbours told CBC News the three were a family; a mother and two children in their late teens or early 20s lived there. Neighbours said they were shocked by the tragedy.

One neighbour, Karen Rogers, said she found the family friendly.

"It makes me feel sad because it could happen to anybody," she said.

Fire safety officer Claudio Mostacci said that the Hamilton Fire Department received a call about the fire at 36 Laird Dr. at 12:22 a.m. and found "heavy smoke conditions" when they arrived minutes later. He did not disclose the victims' names or ages. 

"In the course of search and rescue we did come across three individuals who were brought outside. One person did succumb to their injuries from the fire and was pronounced on scene," he said.

The two other people were transported to hospital, where both were pronounced dead. Hamilton police's arson unit and criminal investigators are also involved.

Dulce McCready, another neighbour, became emotional when asked about the fire. Her neighbours were quiet, she said.

"It's very hard," she said. 

Mostacci said that the fire was contained to one home. CityHousing Hamilton, the city's largest social housing provider, owned the home. 

The Ontario Fire Marshal's office is responsible for conducting fire investigations when certain conditions are met, including when a fire results in fatalities.