LOS ANGELES Whitney Houston, who ruled as pop music's queen until her majestic voice and regal image were ravaged by drug use, erratic behavior and a tumultuous marriage to singer Bobby Brown, died Saturday. She was 48.

Beverly Hills police Lt. Mark Rosen told KABC-TV that Houston was pronounced dead at 3:55 p.m. (6:55 p.m. EST) in her room at the Beverly Hilton. Her body remained in the hotel and Beverly Hills detectives were investigating.

"There were no obvious signs of any criminal intent at this time," Rosen said.

Houston's publicist, Kristen Foster, said the cause of death was unknown.

Houston's death came on the eve of music's biggest night - the Grammy Awards. It's a showcase where she once reigned, and her death was sure to cast a heavy pall on tonight's ceremony.

Houston was supposed to appear at a gala Saturday hosted by her longtime mentor Clive Davis.

She had been at rehearsals for the show Thursday, coaching singers Brandy and Monica, according to a person who was at the event but was not authorized to speak publicly about it. The person said Houston looked disheveled, was sweating profusely and liquor and cigarettes could be smelled on her breath.

Rosen said police received a 911 call from hotel security about Houston at 3:43 p.m. (6:43 p.m. EST) Saturday, and paramedics were already at the hotel because of a Grammy party. Paramedics unsuccessfully tried to resuscitate the singer, the lieutenant said.

Perfect voice, image

At her peak, Houston was the golden girl of the music industry. From the mid-1980s to the late 1990s, she was one of the world's best-selling artists. She wowed audiences with effortless, powerful and peerless vocals that were rooted in the black church but made palatable to the masses with a pop sheen. Her success carried her beyond music to movies, where she starred in hits like "The Bodyguard" and "Waiting to Exhale."

She had the perfect voice and the perfect image: a gorgeous singer who had sex appeal but was never overtly sexual, who maintained perfect poise. She influenced a generation of younger singers, from Christina Aguilera to Mariah Carey, who when she first came out sounded so much like Houston that many thought it was Houston.

But by the end of her career, Houston became a stunning cautionary tale of the toll of drug use. Her album sales plummeted, and the hits stopped coming; her once serene image was shattered by a wild demeanor and bizarre public appearances. She confessed to abusing cocaine, marijuana and pills, and her once pristine voice became raspy and hoarse, unable to hit the high notes as she had during her prime.

"The biggest devil is me. I'm either my best friend or my worst enemy," Houston told ABC's Diane Sawyer in an infamous 2002 interview with then-husband Brown by her side.

It was a tragic fall for one of the top-selling artists in pop music history, with more than 55 million records sold in the United States alone.

Born to sing

Houston seemed to be born into greatness. She was the daughter of gospel singer Cissy Houston, the cousin of 1960s pop diva Dionne Warwick and the goddaughter of Aretha Franklin.

Houston first started singing in the church as a child. In her teens, she sang backup for Chaka Khan, Jermaine Jackson and others, in addition to modeling. It was around that time when music mogul Clive Davis first heard Houston perform. Houston made her album debut in 1985 with "Whitney Houston," which sold millions and spawned hit after hit. "Saving All My Love for You" brought her her first Grammy, for best female pop vocal. "How Will I Know," "You Give Good Love" and "The Greatest Love of All" also became hit singles. Another multiplatinum album, "Whitney," came out in 1987 and included hits like "Where Do Broken Hearts Go" and "I Wanna Dance With Somebody."

A pop darling

The New York Times wrote that Houston "possesses one of her generation's most powerful gospel-trained voices, but she eschews many of the churchier mannerisms of her forerunners."

Her decision not to follow the more soulful inflections of singers like Franklin drew criticism by some who saw her as playing down her black roots to go pop and reach white audiences.

Some saw her 1992 marriage to former New Edition member and soul crooner Bobby Brown as an attempt to refute those critics. It seemed to be an odd union; she was seen as pop's pure princess while he had a bad-boy image, and already had children of his own. (The couple had a daughter, Bobbi Kristina, in 1993.) Still, her moving 1991 rendition of "The Star Spangled Banner" at the Super Bowl, amid the first Gulf War, set a new standard and once again reaffirmed her as America's sweetheart.

'Bodyguard' to downfall

In 1992, she became a star in the acting world with "The Bodyguard." Despite mixed reviews, the story of a singer (Houston) guarded by a former Secret Service agent (Kevin Costner) was an international success. It also gave her perhaps her most memorable hit: a searing, stunning rendition of Dolly Parton's "I Will Always Love You," which sat atop the charts for weeks. It was Grammy's record of the year and best female pop vocal, and the "Bodyguard" soundtrack was named album of the year.

She returned to the big screen in 1995-96 with "Waiting to Exhale" and "The Preacher's Wife." Both spawned soundtrack albums, and another hit studio album, "My Love Is Your Love," in 1998, brought her a Grammy.

But during these career and personal highs, Houston was using drugs. In an interview with Oprah Winfrey in 2010, she said by the time "The Preacher's Wife" was released, "(doing drugs) was an everyday thing."

In the interview, Houston blamed her rocky marriage to Brown. They divorced in 2007.

Houston staged what seemed to be a successful comeback with the 2009 album "I Look To You." The album debuted on the top of the charts, and would eventually go platinum.

Things soon fell apart. A concert to promote the album on "Good Morning America" went awry as Houston's voice sounded ragged and off-key. She blamed an interview with Winfrey for straining her voice.

A world tour launched overseas, however, only confirmed suspicions that Houston had lost her treasured gift, as she failed to hit notes and left many fans unimpressed; some walked out.

Canceled concert dates raised speculation that she may have been abusing drugs, but she denied those claims and said she was in great shape, blaming illness for cancellations.