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Emergency crews have found the body of a four-year-old girl who was swept away after a water bladder atop a dam wall burst in central Queensland.
The Blackwater girl was swept down the MacKenzie River when the bladder, holding at least 6000 megalitres of water, ruptured at the Bedford Weir near Blackwater, about 200km west of Rockhampton, at about 4.30pm (AEST) on Sunday, police said.
Search crews located the girl's body around 6.20am (AEST) on Monday, approximately 800m down stream from the weir.
It is believed the girl had been visiting the weir with her mother and two adult friends, a man and woman, when all four were swept away by the influx of water, police said.
A State Emergency Service (SES) flood boat rescued the three adults on Sunday night, with one of the women found clinging to a tree.
The police investigation is continuing and a report will be prepared for the coroner.
Queensland Premier Anna Bligh has ordered a top priority report into the incident.
Ms Bligh said authorities had yet to explain what may have caused the bladder to burst.
"This was a group of families out having a picnic on a Sunday afternoon," Ms Bligh told the ABC, speaking before police announced that the girl's body had been found.
"We are really at a loss to understand what's happened here but investigators are on the scene now, looking at what may have caused this problem.
"Those investigations will be very thorough, I have directed that I want a full structural engineering report.
"If there's anything here that we can learn on the security of other water storages then of course we've got an obligation to do so."
In a separate incident, three men walking along the weir wall were also swept away on Sunday night and had to be rescued by the SES flood boat.
The bladder on top of the weir's wall permits more water to be stored.
