A man who failed to return from a fishing trip and the subsequent discovery of human remains inside a crocodile will be the subject of a coronial investigation.
A second crocodile has been killed for an autopsy after a 69-year-old fisherman went missing in central Queensland.
The reptile, measuring about three metres, was caught and euthanised by Department of Environment and Science officers near Hinchinbrook Island on Sunday night.
It comes after human remains were found inside a 4m-long animal caught on Saturday in Gayundah Creek near where the man went missing.
Tests to establish if the second croc contains human remains are underway, police say.
"The testing will take place and that information will be provided to the coroner," acting Inspector Andrew Cowie said on Monday.
The man went fishing about 3pm on Thursday and was due back within an hour but failed to return.
Officers found his upturned boat about 2.30am on Friday, with damage suggesting a crocodile attack.
Searchers found human remains in the creek before finding the first crocodile.
Premier Annastacia Palaszczuk says the man's death is shocking.
"It's an absolute tragedy, what happened to that man and can I pass on our condolences to his family. Absolutely horrific," she told reporters.
It's the third crocodile attack in Queensland this month, with two swimmers in Cairns and Weipa surviving encounters.
The animals involved were either killed or relocated to a crocodile farm.
Opposition Leader David Crisafulli said he understood the dangers of crocodiles in Queensland waterways and the importance of awareness programs.
But he said the department had become sluggish at removing problem animals.
"What I am saying now he said people should come before crocs and the culture of the department must be to remove problem animals far quicker than what they are," Mr Crisafulli said.
Federal MP Bob Katter says the state's reactive crocodile-management plan has cost a human life and put others at risk.
Katter's Australian Party wants reptiles removed from populated locations and higher rates of harvesting eggs to control the "exploding" population.
"We aren't talking about a crocodile issue; we are talking about the value of human life," he said.
Ms Palaszczuk said the government's $6 million crocodile awareness program needed to ensure people were aware of sightings and the dangers posed by the animals.
"The locals are aware but I just think that we just need, if there are sightings, we need to make sure that the rest of the community knows where they are," she said.