It's hard to say what exactly is going on in this Argentine lower division match from earlier this week. It starts as a pretty routine scuffle between the two teams after a goal is scored, then right when it seems like play is about to resume under the supervision of the police, it starts up again and quickly turns into a minor riot/stampede.
Everyone gets involved -- even the fans -- as tables are trampled and people are kicked in the head. Then, just as quick as it started, it all loses steam and turns into a bunch of people just standing around. And that's how they keep from getting bored during halftime.
Video via Brasil Mundial