Here in the US, there are places where predatory, carnivorous/omnivorous animals that aren’t native to the area are kept in captivity: zoos, unethical animal habitats (think: Joe Exotic), quasi-ethical rescue animal habitats, etc. I’m sure that, from time to time, local wildlife (cats & dogs (pets and/or feral), small mammals like squirrels and such, various birds) accidentall meander in to their enclosures.
If a pet/feral cat walked into a big-cat habitat, has she signed her own death warrant? Will the big critters ignore her because she’s so small and no their usual prey? Would a captive gorilla tear a pet/feral dog to shreds for the lulz?
Are there any documented cases of a non-native carnivore/omnivore (great ape, big cat, etc.) killing/eating a local animal?
Warning: the page apparently has a video of the snow leopard, a native of Asia, attacking the squirrel. Article doesn’t say where this happened but the video description on YouTube places it at Micke Grove Zoo in Lodi, California, in 2011.
Google also found plenty of reports for the opposite: local animals mauling zoo animals.