This was only the minority, I was with a big a crowd in Albert Square watching it on the large screens and there was no trouble and a very good night.
I think what caused the trouble in Picaddilly gardens was the fact the big screen wasn't working and the police were not letting people out to get to the other places where the screens were, they even put up another screen near the stadium but again they blocked the road and wouldn't let people to the screen.
This is only what I have heard and IMO