I should be in that picture, I never have been able to spot myself though!
If my memory servers me correctly (and I haven't embellished the story with youthful excitement) that was the first bit of fence to go. The coppers started climbing in amongst us lashing out with battens which obviously didn't do much to calm the situation. Then a whole section of fencing went down behind the goal to the right of this pic and the madness really started. By the time they got us all back in, I recall 2 rows of police facing us backed up by mounted police while they tied up some crowd barriers to make a temporary fence, while being heckled with "what the fucking hell is that" or similar.