Sydney - A five-metre crocodile has put on a spectacular display for a passing tour boat, attacking and chomping on a smaller croc before plunging it into an unsurvivable "death roll".
British trainee guide Nikki Davies said one or two of the fearsome predators were usually spotted during cruises in the Kakadu region of northern Australia.
But as the boat went past two crocodiles close together during Friday's sunrise cruise, it became evident that this was no usual encounter, with the larger dominant animal holding a two-metre-long victim clamped in its jaws.
"It had its teeth sunk into the eyes, and snout and brain of the smaller one," Davies told AFP, adding that the little crocodile was struggling in vain to escape.
The larger reptile, known as Maxi, then dragged its catch through the water in a "death roll" in which the animals spin their victims through water to subdue and dismember them.
"I saw it flip it around and thrash it around... It kind of death-rolled it underwater as well which was quite spectacular."
Davies said the smaller crocodile had likely entered into Maxi's territory and the larger animal decided to show him who was boss of the Yellow River billabong - a stagnant pool of water which runs off a river.
She said the rarely seen event highlighted "the supreme power of nature" and the savage attack had kept the 40 passengers on the cruise mesmerised.
Davies said the remains of Maxi's victim were now rotting on the bank of the billabong, while the aggressor himself could be identified by his bulging belly.