'Naughty Boy': Six-metre saltwater crocodile seen eating juvenile croc during Aussie river cruise

Passengers on a river cruise in the Northern Territory could hardly believe their eyes when six-metre crocodile, known as "Dominator", began devouring a juvenile croc within metres of their boat.

The giant reptile, believed to be 80 years old, was seen biting and thrashing its victim on the Adelaide River near Darwin while those on the boat were heard screaming "No! You naughty boy!" and "gross" in graphic footage taken last Friday.

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"If he keeps gobbling up two-metre crocs like the one here, he could eventually grow to being one of the biggest crocodiles in the world", Jake, a representative for The Croc Bus told 9news.com.au

"It's a kind of population control," he said. "This river is infested with crocs every hundred metres.

"And we're just at the end of the breeding season."

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Jake revealed that after four to eight weeks, crocodiles lose their maternal instinct "and in this case, this young croc was seen as prey".

But "Dominator" has reportedly been involved in territorial disputes with another alpha crocodile in the area named "Brutus."

"He's moved down the river, and been getting really aggressive," The Croc Bus team told 9news.com.au.

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