The Eurasian Eagle Owl is truly massive, once seen never forgotten, covering all of Eurasia. They now breed extensively in the wild in the UK, due mainly to falconers and breeders losing their charges. In Norfolk, 6 were ‘released’ when their aviary was demolished in a mini tornado and none were ever recaptured. Now reasonably commonplace. They kill anything, feather or fur.
Still UK bred in captivity, though less common now.