I would strongly dispute "regularly" Graham. Having read extensively on this subject through the books of Jim Corbett, "Maneaters of Kumaon" etc. it's very evident that big cats, 99% of the time, only resort to killing humans when they are incapable, for whatever reason, of hunting their natural prey. The most common reason was gunshot wounds and porcupine quills. These books were set in the 1920s-30s when India had a much larger big cat population than it does today, yet attacks on humans were still rare, some areas going 30 years between reported incidents, despite a healthy tiger and leopard population. So I wouldn't consider a lack of attacks on humans in the UK as any sort of evidence that they don't exist.