Feral cats have been let loose in New York City in an attempt to control the city's rat problem.
A group of volunteers trained by the NYC Feral Cat Initiative traps wild cat colonies, spays, neuters and vaccinates them and lets them go again.
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The programme is run through the privately funded Mayor's Alliance for NYC Animals - a coalition of more than 150 animal rescue groups and shelters.
It estimates as many as half a million feral and stray cats roam New York's five boroughs.
Feline rat patrols keep an eye on the city's delis and other food outlets.
The Human Society of New York and the ASPCA provide the spaying and neutering of these cats free of charge.