the video was taken by tim falby. this is like an annual keg party. thousands of people out on the streets. this was back on march 24th. on the rooftop. >> exactly, nick. on the rooftop. >> i think the entire college is there. >> yeah. notice the roofs they're dancing and jumping around on. not too sturdy. that guy is, like, banging on a portion of the roof that is looking like it's about to break off. >> i think you may be able to predict what happens next. >> yes. >> oh. >> as you can see, an entire portion of this sort of red-colored roof drops down. looks like about a yard. but they almost react and just keep the party going. they kind of stay on the thing, keep dancing. the landlord, he just repaired this roof six months ago. so two roofs need repair. one will cost about $4,000 to fix. >> oh. >> this is one dude that didn't even get off the phone. did you notice that? in the bucket hat. hey, the roof just collapsed. one guy, after the roof collapses, he gets back on. one report does say throughout the day there were 15 arrests, 80 people were tre