(LOS ANGELES) -- Authorities are investigating what caused the death of legendary singer Whitney Houston, who captivated audiences with her powerful voice while battling drug use and a rocky marriage with Bobby Brown.
On Saturday, paramedics found a lifeless Houston inside her hotel room bathtub at the Beverly Hilton hotel. TMZ reported that Houston's aides found her in the bathtub with her face underwater and attempted CPR before calling hotel security.
Officials were also unable to revive her.
WATCH: People magazine’s Kate Coyne discusses the singer’s death.
Beverly Hills police Lt. Mark Rosen said Houston was pronounced dead at 3:55 p.m, adding that there were "no obvious signs of foul play and no obvious signs of a cause of death."
Los Angeles Coroner Office officials left with Houston's body around 1:50 a.m. PT. An autopsy is expected to be finished Sunday but any results will be deferred pending a toxicology report, according to ABC News affiliate KABC.
The coroner's office declined to speculate how Houston died when asked about reports that she may have drowned.
When asked about drugs in the room, Ed Winter, with the Los Angeles County Coroner's office, said he could not comment on it.
A source told KABC that a few presciption pill bottles were found in Houston's room.
Winter also would not comment on the condition of the body or whether Houston was naked or not.
Just hours before her death, Houston's mother, Cissy Houston, and her cousin, Dionne Warwick, reportedly both spoke to the singer and said there was no indication that anything was wrong.
Warwick spoke to her over the phone to check that they were seated at the same table at Davis' party, and Cissy Houston talked to her at around 3:15, TMZ reported.
Houston was staying at the hotel to attend music industry executive Clive Davis' annual pre-Grammy bash.
It is the same event where she was introduced to the record industry nearly three decades ago.
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