Queensland caravan explosion could be 'murder-suicide'

Queensland Police are considering the possibility a deadly caravan blast in Mount Isa was a murder-suicide.

Four-year-old River Hinder and his big sister Nyobi died along with their father Charlie in the explosion at Mount Isa yesterday.

There are reports Charlie had recently separated with his wife.

Police believe at least one of the caravan's gas cylinders fuelled the explosion.

Scientific officers spent the night at the tragic scene investigating the cause of the explosion.

Emergency services are still concerned about the structural integrity of the homes surrounding the explosion site and residents who have been evacuated still cannot return home.

Homicide detectives are flying into Mount Isa from Brisbane to prepare to investigate the deaths.

Mount Isa Mayor Tony McGrady said the deaths would hit the town of 23,000 residents hard.

"These things happen in big cities, to some extent they're anonymous," he said.

"But when they happen in small communities such as ours it's all the more hurtful."

But Mount Isa locals say he was in good spirits the day before the tragedy.

"He ordered a meal for his family, and he told me he'd be a regular"

The explosion rocked houses in the residential suburb of Mornington.

Sonja Wessels, who lives about 500 metres away, saw smoke billowing from the Deighton St property.

"We heard it alright. It rocked the place," she told AAP.

"You could tell it was a pretty big explosion."

Police say the caravan was parked in the front yard of a residential property.

The house was badly damaged after it caught alight.

Mount Isa MP Rob Katter asked the public to keep the victims in their prayers.

Premier Annastacia Palaszczuk has allowed priority use of government aircraft to fly a disaster management team to the town.

"Such young lives lost in such a tragic event," she said.

Federal MP Bob Katter says the explosion warrants an inquiry into the gas industry.

The colourful MP's call comes after the remains of a 39-year-old man, a four-year-old and seven-year-old were found in a caravan that exploded in Mount Isa on Tuesday.

A crime scene has been set up and homicide investigators will arrive from Brisbane on Wednesday.

While the exact cause of the deadly explosion is not yet known, the Kennedy MP pushed for a government-backed inquiry into the gas industry in the wake of the tragedy.

"An industry that makes it so easy to cause personal harm and injury better start looking very hard at itself," he said in a statement.

A spokeswoman for Mr Katter said the MP couldn't specify whether the inquiry should be backed at the federal or state level, but it could follow a format akin to the current Grantham floods inquiry.

A recovery centre was set up at the town's civic centre on Tuesday afternoon.

If you are concerned about the mental health of yourself or a loved one, seek support and information by calling Lifeline 13 11 14, Mensline 1300 789 978, or Kids Helpline 1800 551 800