While the article itself talks about how a camera caught Banksy (though not in any useful way) the video has a much more interesting story. Apparently the nearby Boys Club mentioned removed the Banksy despite the fact it wasn't on there wall and they basically had no claim to it and are now trying to sell it. This seems to me to be a very morally grey area.

Their argument seems to be pretty much "first come first serve" but presumably that wall is owned by somebody who has a much better right to it than these people.

I'll be interested to see if it pans out, especially given that its removal could be considered vandalism itself.