Is there a black panther roaming the streets

of the port district of the city in which I live?
The story came up again in this morning's paper. It is one of those curiosities the paper likes to raise once in a decade or so. I had heard it before. If the panther exists then it is very old indeed. 
How do I know this? I know because my paternal grandfather had his tailoring business in the street  in which people have claimed to see it. He knew about the story - from years before I was born.
Although they never owned one - or any other pet - my paternal grandparents were fond of animals in a no nonsense sort of way. 
They did not believe in "ghosts" or any other form of the supernatural. A great-aunt by marriage once produced some Tarot cards and my grandfather ordered her to take them out of the house. His strict Presbyterian upbringing found them highly offensive. 
But there was the story of the panther. He told it to me one evening when I was in my teens. There were just the two of us in the car. We were going home from the evening church service when he stopped at his place of business to pick up something. I was waiting in the car for him. A mostly black cat crossed the street ahead of the car.  I thought nothing of it.
My grandfather came returned put what he had collected carefully on the back seat. (It was probably a suit he had made.) As he started the car  I saw the cat again and said,
    "Watch out for the cat."
He looked and then grunted and said, "I hope you don't believe that nonsense."
    "What nonsense?"
    "What was the cat like?"
    "Well mostly black but with a white shirt front."
He nodded and told me that some people had claimed to see a black cat as large as a panther going along that particular street. It had supposedly "escaped from a circus".  The story had been going around as long as he could remember and he was by then a very old man. (He worked until he was 86.) 
The story is still there. It is a piece of "urban folklore" that may never die out.