Humble Pie and Jo Jo Gunne,
Milwaukee Summerfest, people rioted, burned beer tents down, police goons came in, formed a line along the lakefront, with batons, no badges, and moved through the crowd, hitting eveyone who didnt move !
We took off, got the hell outta there, many got arrested. Concert was great but not a good time afterwards. As far as I could tell, it all started when the band was playing an encore and someone tossed a bottle or something onto the stage. It hit one of the members and they walked off. Everybody went nuts and the rest is history.

I remember that it rained really hard and the electricity went out for a while.