Pop queen Whitney Houston dies at 48 (Video).

CBSNews - Whitney Houston, who ruled as pop music's queen until her majestic voice and regal image were ravaged by drug use, has died at the age of 48.

Police responded to an emergency call at the Beverly Hilton hotel in Los Angeles at about 3:45 p.m. PT, said Lt. Mark Rosen with the Beverly Hills police. Paramedics who were already at the hotel because of a Grammy party rushed to Houston's fourth-floor suite and attempted to revive her but they were unsuccessful, Rosen told KABC-TV.

Houston was pronounced dead just before 4 p.m., Rosen said. Her body remained at the hotel while detectives were investigating.

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

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

Her 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 Sunday's ceremony.

Houston's longtime mentor Clive Davis held his annual pre-Grammy concert and dinner Saturday at the Beverly Hills Hilton. It was a bizarre scene as stars walked the red carpet amid a heavy police presence while news vans snaked around the block and paparazzi staked out every hotel exit.

Stars including Dr. Dre, Adam Lambert, Serena Williams and Kim Kardashian were in attendance. Producer Jimmy Jam, who had worked with Houston, said he anticipated the evening would become a tribute to her, and he expected there to be one at the Grammys as well.

Houston was supposed to appear at the gala, and Davis had told The Associated Press that she would perhaps perform: "It's her favourite 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.

At her peak, Houston was the golden girl of the music industry. From the middle 1980s to the late 1990s, she was one of the world's bestselling 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 such as 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.