How singer Whitney Houston died at the Beverly Hilton Hotel on Saturday is still being investigated by authorities, who said there were no obvious signs of foul play or cause of death at this time. The 48-year-old singer was found dead in her room on the fourth floor.

Beverly Hills (Calif.) Police Department Lt. Mark Rosen told the media that the singer was pronounced dead at 3:55 p.m. in her room. "No obvious signs of foul play and no obvious signs of a cause of death," Rosen told the media. A coroner will determine the facts of the matter.

TMZ has reported that prescription drugs were present and that it is "possible the singer drowned in the bathtub." Sources told the celebrity news Web site that when EMTs got to the scene Houston's body was already removed from the bathtub. That report added that Beverly Hills cops found various pill bottles but there wasn't any evidence that Houston was drinking alcohol in the room.

Some reports have said singer Ray J found Houston's body in the room. Others have said that a bodyguard found the singer's body.

However, Rosen could not confirm either assertion to the media at this time, but said, "Someone in her entourage found her unresponsive in her room."

The police representative also said it is unclear who notified the hotel staff. He added that the singer had an entourage at the hotel.

An attempt was made to resuscitate the singer, but medics were unsuccessful.

Rosen could not comment as to whether drugs were found in the singer's room.

"We don't know yet," he told the media. "Her death is under investigation."

Houston's death came on the eve of the annual Grammy Awards shows, the biggest night in music. She was scheduled to attend her mentor Clive Davis' yearly pre-Grammy gala at the Hilton.

The Los Angeles Times reported that on Thursday Houston stopped by the rehearsals to give vocal tips to Brandy and Monica, who were going to be the headliners at the pre-Grammy gala on Saturday. The Times stated that Houston, though smiling, looked disheveled in mismatched clothes and that her hair was dripping wet with either sweat or water.

Houston also reportedly showed erratic behavior throughout that afternoon, "skipping around the ballroom in a child-like fashion and wandering aimlessly about the lobby," the Times reported, adding that the singer also smelled of alcohol and cigarettes.

A Grammy staffer told the Times that the singer was dancing off camera to make the other singers and Davis laugh. Houston's daughter Bobbi Kristina Houston Brown reportedly pulled her out of the room.

Paparazzi caught Houston later that day leaving a Hollywood nightclub with what looked like blood on her leg.

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