Whitney Houston was reportedly killed by a cocktail of prescription drugs and alcohol.
The 48-year-old singer was found dead in the bathtub of her Beverly Hills hotel room on Saturday (11.02.12) and while it was initially thought she had drowned, officials have now told her family she may have died before she became fully submerged in the water following a drink and drugs binge.
It is believed only a small amount of water was found in her lungs, which medics claim was not enough for her to have drowned.
Investigators are also working on the theory she suffered a heart attack caused by an adverse reaction to her medication.
Los Angeles police - who obtained a search warrant for the fourth-floor suite at the Beverly Hilton Hotel - are said to have found six prescription pill bottles, Xanax, Lorazepam, Ibuprofen, Midol, Amoxicillin and Valium.
Now detectives investigating her tragic death will question up to nine doctors they believe could have supplied her with the lethal cocktail of prescription drugs.
They want to know how the mother-of-one - who had a history of drug and alcohol abuse - was able to get hold of such a vast quantity of substances
A source said: "Investigators will speak to her doctors. Even though it appears to be prescription pills that may have killed her as opposed to illegal street drugs, the authorities need to be satisfied she had these drugs in her possession legally.
"They need to determine that no one is criminally negligent. There could still be charges in this case."
A postmortem on Whitney's body was carried out on Sunday (12.02.12) but officials say they will not have any definitie answers about the cause of death until drug tests are completed, which could take weeks.
The 'I Will Always Love You' hitmaker's funeral is set to take place on Friday (17.02.12) in Newark, New Jersey.
