Australian park rangers said on Friday they had caught the year\'s biggest crocodile, a whopping 4.5 metres (15 feet) beast which had been terrorising fishermen. The monster croc was harpooned overnight at a waterhole northeast of Darwin in the Northern Territory, where it was first reported to have lunged at the side of a boat a fortnight ago. Since then it had reportedly menaced a number of other anglers, said ranger Joey Buckerfield. \"I think because it is such a big size and it seems to be the only croc in that area, it might just feel threatened by boats,\" he told public broadcaster ABC. Slightly longer than a 4.5-metre croc nabbed in February, the creature was officially the largest catch in the Northern Territory for 2011, he added, where close to 200 of the maneaters have been trapped since January. An average of two people are killed each year in Australia by saltwater crocodiles, known locally as \"salties\", which can grow up to seven metres (23 feet) long and weigh more than a tonne.