It was a few years ago. Enough that I can't exactly remember how it looked. It was a very old house, made out of wood. It was dangerous to have any sort of event, as the danger of the building caving in was extreme, but my family, being from the deep south, didn't take that precaution.
It was somebody's birthday party, which very conveniently fell near Halloween. So, we rented out an old, abandoned house, and used it like a walk-through horror attraction. We picked a few family members to put on masks and hide behind certain furniture. It was fun while it lasted, but what would happen the next day, was not a laughing matter.
Three people went to clean up after the party the next day. I don't remember exactly what happened, but I know that one of them was walking in front of a bookshelf when it tipped over, crushing their leg and pinning them to the ground. They were okay, but our family has never been in or near that house again.