Whitney Houston was found in a hotel bathtub, a coroner's official confirmed Sunday evening, saying it could be weeks before it is clear exactly how the singer died.

Assistant Chief Coroner Ed Winter told reporters that his office will not release any information from an autopsy conducted on Houston's body at the request of detectives investigating the singer's death.

According to Winter, toxicology tests that will help officials determine a cause of death will not be in for weeks.

The confirmation followed reports from earlier Sunday suggesting that members of Houston's entourage found her facedown in a bathtub in her room at the Beverly Hilton Hotel Saturday afternoon.

Citing unnamed sources, celebrity news website TMZ reported that the pop diva's stylist, hairdresser and two bodyguards were present when she was pulled from a tub at the hotel.

Foul play is not suspected in the singer's death.

Beverly Hills Police Lt. Mark Rosen said Sunday his agency may release more details about its investigation on Monday, but that will depend on whether investigators feel comfortable doing so.

TMZ reported earlier Sunday that on the afternoon she died, Houston's entourage grew concerned when they realized she had been in the washroom for over an hour. Knocks on the door reportedly produced no answer from the pop star.

The site writes that the hairstylist entered the washroom and screamed upon seeing Houston whose "face was below the water and her legs were up."

TMZ also reported that "law enforcement sources" said police retrieved about half a dozen pill bottles from Houston's room, which included Xanax. No illegal drugs were cited in the report.

Winter would not confirm what police found in Houston's room. He said while there were no signs of trauma to Houston's body, officials were not ruling out any potential cause of death.

On Sunday morning, paramedics took Bobbi Kristina Brown, Houston's 18-year-old daughter, to a Los Angeles hospital to be treated for stress and anxiety, a source close to the family told The Associated Press.

The Beverly Hills Fire Department confirmed that paramedics took Brown to hospital around 10:30 a.m. Sunday. She was later released.

It has been reported that Brown had been staying at the Beverly Hilton Hotel, where her mother died. She had accompanied Houston to several pre-Grammy events last week.

Houston, who built a larger-than-life music career amid drug use and a troubled marriage, died on the eve of the Grammy Awards. The megastar had been expected at an annual pre-Grammy party on the night of her death.

Several tributes were planned to honour the life of one of music's biggest divas on what is largely considered music's biggest night. Grammy organizers say Houston, a six-time trophy winner herself, will be remembered in a tribute by singer Jennifer Hudson.

High-profile tributes to Houston began rolling in hours after her publicist confirmed her death.

Renowned producer and mentor Clive Davis decided to go on with a concert planned at the Beverly Hilton, dedicating the evening to Houston. At one point, he paused his performance and asked for a moment of silence. All was quiet as audience members looked at a projected image of Houston gazing towards the sky.

Friends and family say Houston was in good spirits in the days leading up to her death. She appeared with singer Kelly Price at a Hollywood club on Thursday, singing the gospel hymn "Yes, Jesus Loves Me."

"She was happy," Price told the Associated Press. "She was the Whitney I always knew."

Though Houston was a portrait of strength on stage and on-screen, the details of her personal life reveal a much more fragile woman. She grappled with a dependence on cocaine, marijuana and other drugs. The destructive behaviour seemed to escalate when her marriage to fellow singer Bobby Brown fell apart amid abuse allegations.

"The biggest devil is me. I'm either my best friend or my worst enemy," Houston told ABC's Diane Sawyer in a 2002 interview.

Decades after Houston topped the charts with "Saving All My Love for You" and starred In "The Bodyguard" alongside Kevin Costner, onlookers began to wonder if the diva's fabled voice and energy were fading.

On Thursday, Houston attended a rehearsal for a pre-Grammy event to coach singers Brandy and Monica. An unnamed event attendee told The Associated Press said the songstress was sweating profusely and smelled of cigarettes and liquor.

In a Forbes online article, Friedman wrote that a hotel patron complained of a leak from Houston's suite one night before the pop star's death. According to the report, the unnamed man insists the water was cascading from Houston's overflowing bathtub.

Hours after her death, Houston's estranged husband Bobby Brown took to a stage in Mississippi, visibly upset. He professed his love for his late ex-wife before performing hits such as "My Prerogative" and "Mr. Telephone Man."

In a statement issued Sunday, Bobby Brown thanked the public for their condolences but asked that he and his family be given time to mourn.

"I am deeply saddened at the passing of my ex-wife, Whitney Houston," the note began. "At this time, we ask for privacy, especially for my daughter, Bobbi Kristina."

Brown was said to be making his way to Los Angeles to be with his daughter.

Bobbi Kristina was born in 1993, about a decade before Houston called police alleging Brown had abused her. Reports indicate she was found with a cut lip and bruised cheek.

After 15 turbulent years of marriage, Brown and Houston divorced in 2007.