Determining how Whitney Houston died is expected to take time

While an autopsy on pop star Whitney Houston could occur in the next day, it is likely to take weeks before the L.A. County coroner's office makes an official cause-of-death ruling.

Both the Beverly Hills Police Department and Los Angeles County coroner's office are investigating Houston's death. No cause has been established, and authorities said Saturday night it's too early to determine whether she died of natural causes.

"There were no obvious signs of criminal intent," Beverly Hills Police Lt. Mark Rosen said.

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Houston had drug and alcohol problems for years, and last May her spokeswoman said she was going back into rehab. The Times reported that days before her death, she had been acting strangely, skipping around a ballroom and reportedly doing handstands near the hotel pool. According to The Times' Gerrick D. Kennedy, Houston greeted people with a warm smile but appeared disheveled in mismatched clothes and hair that was dripping wet.

Police said at this stage of the probe, they do not have evidence that drugs played a role in Houston's death.

In other cases of high-profile figures dying unexpectedly, the death investigations lasted for months and included detailed toxicology tests.

It took nearly three months for the coroner to officially rule on the death of Michael Jackson in 2009. In that case, authorities extensively reviewed the various prescription drugs he was taking, interviewed his doctors and examined his medical history. The coroner ultimately determined he died of "acute propofol intoxication."

The coroner's office took about a month to rule that rapper Heavy D's unexpected death last year was caused by a blood clot.

Houston's death came as she was in the Los Angeles area to attend music executive Clive Davis’ annual pre-Grammy party Saturday at the Beverly Hilton.  She had performed at another pre-Grammy event earlier this week.

Police said people in Houston's party called paramedics. Some firefighters were already in the hotel working the gala, and they tried to revive her.

Paramedics performed CPR for about 20 minutes before the pop star was declared dead.

The Beverly Hills Fire Department said it was called to the hotel about 3:30 p.m. and Houston was pronounced dead at 3:55 p.m.

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Photo: Photographers crowd around a coroner's van as it leaves the Beverly Hilton Hotel early Sunday. Credit: Mark J. Terrill / Associated Press