TALLAHASSEE, Fla. - Rescue workers and police found a scene of total chaos after the floor of a second-floor apartment collapsed under a late-night party in Tallahassee, Fla.

The Tallahassee Democrat reports investigators still don't know what caused the floor to give way early Sunday. Officials say 55 people were injured.

City inspectors and other officials plan to comb through the rubble Monday to try to learn what happened. Damage is estimated at $250,000.

Officials say about 100 people were thought to have been inside the four-bedroom apartment when the floor gave way.

Tallahassee police spokeswoman Anitra Highland says most of the injuries were "broken bones and sprains."

The apartment complex was built in 1995.