I read about this on Facebook last night.
As William said, a few were originally released by the health unit and as a few became hundreds irresponsible owners used it as a dumping ground for unwanted pets.
There were getting on for 1000 but now there's none left apart from around 60 that were saved.
Food poisoned with antifreeze was allegedly left and also it is believed the warrens were gassed or poisoned in some way.
I feel this is as bad, if not worse, than Australia releasing RVHD viruses into the wild rabbit population.
I'm so upset and angry about this. A group "Bunnies matter in Vegas" have been rescuing and looking after these rabbits and I've just seen a bit of heartbreaking video of some of the group collecting the poor little bodies. I had to switch off as couldn't bear it.
It's not known if it was done 'officially' or some sick individual after a newscast saying the rabbits were out of control, sick and a hazard to human health.