Two boys aged three and five have been found dead, hours after they went missing from a home in the Townsville suburb of Cranbrook, near the Ross River.
Police are trying to piece together the final hours of two young brothers whose bodies were found close together in a flood-ravaged Townsville river.
The boys, aged three and five, were located around dawn after more than 100 police, SES workers and residents joined a frantic 12-hour search in suburban Cranbrook.
The boys' relatives called police about 6.30pm on Monday, asking for help after the children didn't come home.
Police found their bodies, sometime between about 4.30am and 6am on Tuesday, in a deep, cutaway section of the Ross River.
The adjoining bank was steep from the power of record floods that hit Townsville about a month ago and there was still vegetation in the water.
The boys' devastated mother has been swamped by heartfelt messages of support on Facebook, after she earlier spoke of her emptiness as police searched for her boys.
“It's just a dreadful tragedy," Gracelyn Smallwood, a family spokesperson said.
"I want to thank all of those amazing people last night, Christians, Muslims, black and white, people from all different backgrounds that were here last night and searching for these two little precious children. Because all children are precious."
Police are talking to witnesses, including some who said the boys were seen jumping into the river, a place they often went to play with other children from their neighbourhood.
"Obviously we have young boys who are very familiar with their surroundings."
They, like other children, play in the community," Detective Senior Sergeant Dave Miles told reporters on Tuesday.
"We have to look at all circumstances at this point before we make any determinations as to whether or not there's anything we should be concerned about. It could be as innocent as harmless play that's had tragic consequences."
Support is being offered to the boys' family, and to the officers who found the bodies.
"The best way to describe the family is devastated, as you'd expect," Snr Sgt Miles said.
"They were located in very close proximity to each other. They were in a small, cutaway area in the river. From the recent flood events, it's quite deep and quite a steep bank and there's some vegetation there."
Locals have been praised for helping police and SES workers search yards and local streets after an amber alert for the boys was issued on Monday evening.
A report will be prepared for the coroner.
"The coroner will ultimately make a determination if there's any concerns that they have," Snr Sgt Miles said.
Townsville Aboriginal academic and activist Gracelyn Smallwood said there was deep shock in the city's Indigenous community.
"Townsville's had such a tragedy with the floods and we're just coming to terms with so many of our people in town losing property," she told the ABC.
"But nothing can take the place of this terrible loss, of two little innocent children who regularly come and play in the park."
Premier Annastacia Palaszczuk said the boys set off an adventure and didn't come home.
"In the last month the people of Townsville have had to endure a lot of heartache and wrenching despair - and now, they must endure more," she said.
Anyone with further information should contact Crime Stoppers on 1800 333 000.
SBS News will not show images or name the children due to cultural protocols.