Houston was found dead today at the Beverly Hilton

Houston was found dead today at the Beverly Hilton

No illegal drugs have been found in the hotel room where Whitney was found dead, but it is possible that the singer drowned in the bathtub.  Sources tell TMZ that when EMTs arrived Whitney's body was already removed from the bathtub so it will take an autopsy to determine if she OD'd, drowned or died from some other cause.

Informed sources tell us ... Beverly Hills cops -- who were still searching the room at the time this story was posted -- found various pill bottles.  There was no evidence that Whitney was drinking alcohol in the room