Police rescued a girl, 11, from the burning home moments before it exploded at Beerwah on the Sunshine Coast on Tuesday.
Officers have not confirmed reports she was tied to a chair.
Police had spoken to a man at the house shortly before the blast and neighbours said officers had been evacuating people from their homes before the drama unfolded.
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The house has been reduced to a charred pile of rubble from the force of the blast, which was felt up to 300 metres away.
Police have not released any details about the dead man.
Alice King, who lives nearby, said it was lucky no one else was killed.
"It was just the time of the afternoon. There was a lot of school kids running around and standing there watching," she told ABC Radio.
The house is now a crime scene, and the Ethical Standards Command will investigate the role of police in the incident.
