A Queensland man has been left with a decades-old mystery on his hands after discovering a surgical plate inside a crocodile's stomach.
The crocodile farmer says the piece of surgical steel belonged to a person or pet.
And now he's trying to find out "who."
When your stock consists of 5000 crocodiles, surprises come aplenty on this Queensland farm.
But nothing could prepare John Lever for what he found in the stomach of one dead croc.
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The 4.7-metre monster had something or someone's remains inside.
"Strange things turn up in Crocodile's stomachs all the time we have always a look when we get a large crocodile that dies, but finding a surgical plate in there was, well, we never thought we'd find that," said John Lever, from Koorana Crocodile Farm.
The surgical plate and screws are still intact but the serial number's been destroyed by stomach acid.
Lever has traced the manufacturer to Sweden. The question now, to whom did it belong?
"It's eaten something with a plate in it, either a human or a pet."
In Queensland, crocodiles kill a human about once every three years. But this plate could've been in its stomach for decades.
Surgeons say it's an older model and the crocodile is 50 to 70 years old.
"This is an old croc, it wasn't a young fella," said Lever.
He's appealing to the public for answers and is happy to turn the plate over to police.
A clue from the belly of a cold-blooded killer, which could see a cold case finally solved.