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

Beverly Hills police Lt. Mark Rosen said Houston was pronounced dead at 3:55 p.m. in her room on the fourth floor of the Beverly Hilton. A Los Angeles County coroner's official said the body remained in the building late Saturday. "There were no obvious signs of any criminal intent," Rosen said.

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

Rosen said police received a 911 call from hotel security about Houston at 3:43 p.m. Saturday. Paramedics who were already at the hotel because of a Grammy party were not able to resuscitate her, he said.

Houston's death came on the eve of music's biggest night - the Grammy Awards. It's a showcase where she once reigned, and where she will be remembered Sunday in a tribute by Jennifer Hudson, organizers said.

Her longtime mentor Clive Davis went ahead with his annual concert at the same hotel where her body was found. He dedicated the evening to her and asked for a moment of silence as a photo of the singer, hands wide open, looking to the sky, appeared on the screen.

Houston was supposed to appear at the gala, and Davis had told The Associated Press that she would perhaps perform: "It's her favorite night of the year ... (so) who knows by the end of the evening," he said.

Houston 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.

Two days ago, she performed at a pre-Grammy party with singer Kelly Price. Singer Kenny Lattimore hosted the event, and said Houston sang the gospel classic "Jesus Loves Me" with Price, her voice registering softly, not with the same power it had at its height.

Lattimore said Houston was gregarious and was in a good mood, surrounded by friends and family, including daughter Bobbi Kristina.

"She just seemed like she was having a great night that night," said Lattimore, who said he was in shock over her death.

Aretha Franklin, her godmother, also said she was stunned. "I just can't talk about it now," Franklin said in a short statement. "It's so stunning and unbelievable. I couldn't believe what I was reading coming across the TV screen."

The Rev. Al Sharpton said he would call for a national prayer Sunday morning during a service at Second Baptist Church in Los Angeles. "The morning of the Grammys, the world should pause and pray for the memory of a gifted songbird," Sharpton said in a statement.

In a statement, Recording Academy President and CEO Neil Portnow said Houston "was one of the world's greatest pop singers of all time who leaves behind a robust musical soundtrack spanning the past three decades."

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 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.

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