Ontario's Office of the Fire Marshal has determined there were no working smoke alarms in an Oshawa multi-resident dwelling that caught fire Monday, killing four people, including a mother and her two children.

Autopsies have been completed on the victims. Officials say all four died from smoke inhalation. 

The blaze broke out shortly after 8 a.m. at the house on Centre Street North and Colborne Street West, near Bond and Simcoe Streets, Oshawa Fire Services said. 

Lindsey Bonchek, 36, and her daughter Madeline, 9, died in the fire that gutted the two-storey home. Bonchek's son, Jackson, 4, was pulled from the fire but later died.

bonchek family fire

Lindsey Bonchek, 36, and her daughter, Madeline, 9, were trapped inside the house. Bonchek's four-year-old son, Jackson, was pulled from inside the home and later died in hospital. (Lindsey Bonchek/Facebook)

Steve Macdonald, 50, managed to escape the fire with his pregnant daughter, but ran back into the building to rescue others, according to his family, and did not come out.

Ontario Fire Marshal investigator Richard Derstroff said Wednesday the fire originated in the kitchen on the main level of the home, and that there were no working smoke alarms within the structure.

4 dead including 2 children in Oshawa, Ont., house fire1:10

"It's very frustrating," Derstroff said. "I'm at a loss for words. The law has been in place for a long time, it's not like people don't know about this.

"It becomes frustrating when fire safety is not taken seriously."

steve macdonald

Steven Macdonald, 50, shown here on the far left, ran into the burning house in an attempt to save those trapped inside, according to his family. (Facebook)

Standing outside the scene of the fire, city councillor Amy McQuaid–England said she had been trying for years to get licensing of rental housing in Oshawa to improve tenant safety.

McQuaid–England said she tabled a motion that would require landlords to renew their license every couple of years and subject the buildings to fire inspections.

"Once it's registered we never go back, so it could be registered in 1993 and we never go back unless there's a complaint from the tenant," she said. "There's no proactive enforcement, there's no looking ahead to make sure that we protect people before something happens."

The motion was ultimately shot down because the city of Oshawa did not want to pay for it, she said.

The fire investigation is ongoing. Officials say natural gas was not involved.

With files from Derick Deonarain