Whitney Houston's final days - CBS News Whitney Houston's death is not considered suspicious, but investigators are still trying to figure out what happened. The Los Angeles County Coroner's Office held a news conference Sunday, but released very little information. Houston was staying at the Beverly Hilton Hotel for a big pre-Grammy party. But then, in mid-afternoon Saturday, a 911 call from the hotel brought an ambulance racing to the scene. Paramedics found Houston unresponsive in her hotel room bathtub. Complete coverage: Whitney Houston: Death of a Pop Diva Special Section: 54th Grammy Awards The hotel was already busy with fans and photographers looking to see recording stars arriving for one of the big gatherings of the Grammy weekend. Instead, they were there as a van from the coroner's office carried away Houston's body. Houston had been in a room on the hotel's fourth floor. At 3:43 p.m., someone in her group asked the front desk to call 911. Paramedics arrived quickly, but at 3:55, Houston was declared dead. There was an autopsy Sunday. "There were no visible signs of trauma," said Ed Winter, assistant chief of the coroner's office, "and foul play is not suspected at this time." But what killed her remains a mystery. "There will be no cause of death at this time," Winter said, "because it is pending toxicology, and that could take up to six-to-eight weeks." Law enforcement sources tell CBS News there were prescription drugs, but no illegal substances found in Houston's hotel room. Houston's struggles with alcohol and drugs over the years were well-known. But those who saw here in the days just before her death say they saw no signs of trouble. "We were still waiting for that great comeback," says singer Kenny Lattimer. He was host of a pre-Grammy party Thursday night when Houston surprised Kelly Price on-stage. "It felt like it was a private moment," says Lattimer, "where she singing, 'Yes, Jesus loves me,' but she was singing it to Kelly, but she wasn't doing it in a way that was particularly for the audience." Pictures taken of Houston as she left the party suggest she was disheveled, sweating, her hair soaking wet. The photos show spots of blood on her leg. But Lattimer has only good memories of the last time Houston sang in public. I felt ... I was looking at a woman who was in good spirits, her natural warm self. ... I just felt like she was happy.