SAN LUIS OBISPO, Calif. (PIX11) — Eight people were injured Saturday morning when the roof of a garage they were partying on collapsed.

San Luis Obispo Fire Department estimates that over 1,000 students from Cal Poly University were in attendance of the school’s unofficial “St. Fratty’s Day” festivities.

About 30-40 people were standing on the roof of a garage when it collapsed. A video posted to YouTube showed the exact moment of the collapse. Of the eight people injured, four were taken to local hospitals. One person was seriously injured who was impaled in the thigh by a piece of wood.

Cal Poly has not released a statement regarding the collapse.