This is not the first story like this I have heard about AirBnB. They have just done a good job keeping them hush hush and talking people out of going to the cops. Obviously stories like this are horrible for their reputation and AirBnB have a big incentive to try and take care of issues on their own.
What in the world do they offer hosts to keep them from going to the police? And what kind of host would contact AirBNB before calling the police? If I came home and my apartment was ransacked, I'd probably be on the phone to 911 before I even set foot inside.