A rescue is underway to save dozens of stray cats abandoned in an area of disused railway land in Joondalup after the Cat Haven successfully launched an appeal through social media for help to get access to the site.
The feral cat colony includes many kittens and some cats that show signs of mistreatment.
A cat trapping exercise on Saturday night netted just seven of the creatures and all had to be put down yesterday after vets declared them diseased.
Spokesman for the Cat Haven David Settelmaier said the cats were lovely animals and he had been shocked to see so many abandoned in one place.
An estimated 40 moggies have been living in an area of land at the back of a shopping precinct off Lawley Court.
Mr Settelmaier said the area was swarming with cats and kittens.
"I've never seen anything like it," Mr Settelmaier said.
"As soon as it got dark, more than 30 cats and kittens appeared out of nowhere and began to look for food."
The bodies of several cats have been found on the nearby train tracks in the past few weeks sparking concerns for the animals' plight.
Mr Settelmaier said the Cat Haven had been trying for months to get access to the site in a bid to rescue the cats but had been stonewalled by the Public Transport Authority.
He said that within a few hours of urging supporters to help lobby the PTA through Facebook and Twitter for access to the site the Cat Haven had been handed the keys.
A spokesman for the PTA said he knew nothing about the allegations but said if access to PTA land was denied it would have been because of safety issues.
The rescue operation is expected to take days.
"We will do our utmost to rehome any cat or kitten that is found to be healthy and not aggressive," Mr Settelmaier.