All the reports say "it is being inestigated, no arrests have been made." I think there may be more to this story than we know or is being reported. Especially since they allowed her to call a friend. I think that if there wasn't a lot of "grey area" to this case they surely would have been arrested and charged immediately. Reportedly, all the men are cooperating with the police investigation...which again indicates to me that there is more going on here. I won't jump to any conclusions until they are actually charged with a crime.
It just seems that if there was physical evidence they would at least have been arrested.