The crocodile reportedly bit a 38-year-old lady within the leg on Monday whereas she was swimming in Butler Cove, Lake Argyle, an space that's dwelling to freshwater crocodiles.
The girl is in a secure situation, Western Australia Well being confirmed.
9News understands the girl was taken to Kununurra Hospital earlier than being transported to Broome Hospital.
She sustained "critical leg accidents" within the unprovoked assault.
A Division of Biodiversity and Conservation (DBCA) spokesperson mentioned workers noticed a freshwater crocodile as much as 2.5m in size within the space yesterday.
"Each the behaviour of a crocodile approaching the boat and the occasions of the day prior to this is per what workers would determine as an issue animal," the spokesperson mentioned.
Wildlife authorities have since "destroyed" the reptile to "guarantee public security".
The DBCA spokesperson added the world is dwelling to a big inhabitants of freshwater crocodiles however they don't seem to be often aggressive except fed or interacted with.
"Whereas not often thought-about to be harmful, animals have the potential to inflict critical accidents," the DBCA spokesperson mentioned.
"The general public is reminded to not feed or strategy wildlife whereas recreating within the Kimberley."