Short answer: No, not in my opinion.
I just think a big cat would be way too smart to get cornered by humans but do seem to occasionally get caught upwind and are glimpsed scarpering away. I remember some lad claiming he got scratched:
"Josh Hopkins, 11, told yesterday how he was playing in a field close to his home in the village of Trelleck, near Monmouth, with his older brother when he spotted what he thought was the family's cat. But it was a much bigger black cat than he had seen before.
"It turned and made a horrible hissing sound. It reared up and lashed at me with its paw, holding my cheek for a second. Then it got my head in its jaws and bit me. I was terrified and I thought it was going to kill me.""
https://www.theguardian.com/uk/2000/aug/26/geoffreygibbs1
Here is poor young Josh after the big cat put his head in its jaws and bit him::
View attachment 78582
Oh no, sorry, wrong URL, here is Josh after the big cat put his head in its jaws and bit him:
View attachment 78581
http://news.bbc.co.uk/1/hi/wales/895643.stm
Make of that what you will...
Unfortunately the media would love big cats to start attacking people in the UK, imagine the headlines and pages they could fill.