Two women and a man are dead after fire tore through a home at Everton Hills in Brisbane's north this morning.
The blaze broke out at the Pavonia Street home about 5:30am, with authorities alerted by a triple-0 call.
Inspector Dan Bragg said neighbours reported hearing an explosion coming from the home.
"What we're advised is that it was quite a large explosion, quite significant, and the neighbour that heard that explosion immediately contacted police," he said.
"We also spoke to one neighbour who gave us advice that there was some yelling beforehand."
Queensland Fire and Emergency Service Inspector Bevan Moore said several witnesses reported hearing "unusual noises".
"Explosions reported by neighbours, the smell of fuel and things like that," he said.
Inspector Bragg said it was believed the fire broke out quite quickly.
"I've heard the fire could be seen from quite a distance away," he said.
"And it was the flames and smoke that actually led people to the address.
"At this stage we do not know what happened here … we have to get to the bottom of it quite soon.
"Screams were heard for help but exactly where those screams were coming from … is yet to be ascertained."
Six crews worked to douse the blaze in the brick home and have now brought it under control.
Inspector Moore said at one point the flames were twice as high as the house.
"You can tell by the damage it was a significant fire and significant heat," he said.
He said crews who were involved would receive support.
"It is difficult for crews when they're confronted with such a tragedy such as this … it does play on people's mind," he said.
Police have evacuated other homes in the suburban street and surrounding areas and closed the road.
But Inspector Bragg said no other homes were damaged.
"Which is quite extraordinary considering the extent of damage to that house and the size of smoke and flames emanating from the residence," he said.
Police say the fire is being treated as suspicious and forensic officers will examine the scene.