Mother under police guard as death toll in Toowoomba house fire rises to three

The death toll from the Toowoomba house fire tragedy has risen to three after two young sisters, critically injured in the blaze, had their life support switched off overnight.

Just after midnight on Wednesday a home on Merritt St in Harristown, Toowoomba, became engulfed in flames.

The ferocious house fire also killed a young boy and injured several family members.

WATCH THE VIDEO ABOVE: Two more children dead after horrific house fire.

Police are now investigating whether the blaze was deliberately lit, with the children’s mother, aged 36, being critically injured and now under police guard in hospital.

“The woman that remains under police guard is the mother to those children,” Detective Superintendent George Marchesini confirmed.

Six people, including four children, managed to escape as the fire took hold however a fifth child did not make it out in time.

Following a search of the property firefighters located a body believed to be that of a nine-year-old boy near the front door of the home.

He has not yet been formally identified.

Five family members were injured in the blaze — including two sisters aged four and seven who were taken to Queensland Children’s Hospital.

The girls passed away overnight after the decision was made to switch off their life support, police confirmed.

A 36-year-old woman who was airlifted to Royal Brisbane Women’s Hospital with serious injuries remains in a critical condition under police guard.

A 34-year-old and 18-year-old man were hospitalised but have since been discharged.

An 11-year-old boy was uninjured.

Detectives say they have not yet been able to interview the children’s mother due to the severity of her injuries.

However, they have spoken to the injured man, who reportedly made frantic efforts to rescue the children.

“The male person that I’ve spoken about, the 34-year-old, is the father of some of those children,” Marchesini said.

“There’s another person that we’ve made contact with from interstate that is a part of that family as well.”

Police won’t confirm if there was any history of domestic violence within the family or if they’d been called to this house before, but say they had some previous interactions with the household.

The fire is being treated as suspicious.

“The house remains a crime scene and is currently being forensically examined as part of Operation Xray Paxton with assistance from the Homicide Investigation Unit,” police sad.“Police are continuing to treat the fire as suspicious, are not looking for anyone else in connection to this incident at this time.”

Acting Superintendent Scott Stahlhut said investigations into the cause of the fire are ongoing.

“We are in the early stages and working closely with forensics and scientific teams to get a clear picture of what happened,” he said.

“We are deeply saddened by this incident.”

“Our hearts go out to the Toowoomba community and to the family and friends involved.”

Queensland Fire Department station manager Neil Goodman said crews who arrived at the scene first were greeted by a “wall of flame and heavy smoke”.

The front area of the house was mostly impacted.

“The guys had quite ... a difficult time making access and getting in to conduct a primary search,” Goodman said.

He said he spoke to one of the family members who was “hysterical” and told crews where the missing child might be.

“We’re all fathers, we’ve all got children, so it’s always hard, it’s a little bit harder when it’s sort of similar to your own situation,” Goodman said.

Neighbour Jennifer Smith described the blaze as “intense”.

“Little children were burnt and they were taken away in the ambulance,” she told 7NEWS.

She said the family were always friendly and the children often played in the front yard.

Queensland Premier David Crisafulli has responded on Thursday to the tragedy.

“We have to do everything we can to make sure that a thorough, a detailed, and a respectful investigation is done.

“We owe that to these kids.

“We are doing everything we can at the moment to make sure that we can give police the resources to deal with domestic and family violence.”

Forensic and fire investigators have returned to the scene as they work to determine exactly what happened.

Anyone who has any information or relevant dashcam or CCTV vision has been urged to come forward.