HOLLYWOOD, Fla. -- It will take anywhere from three to five weeks before coroners will be able to determine what caused the death of Anna Nicole Smith, according to Dr. Joshua Perper, chief medical examiner in Broward Country, Fla.

Perper, who performed the autopsy, said at a news conference Friday that the death could possibly be from natural causes, medications, or a combination of both. He said the autopsy only revealed "subtle findings" in the heart and gastrointestinal tract and blood in her stomach from being in shock before she died.

"There were no findings that would indicate continuing drug abuse," Perper said.

The autopsy found no pills in her stomach, but officials were awaiting the results of toxocological tests that would indicate whether she had taken drugs, said Perper.

Perper added that minor bruises on her back were from a previous fall in the bathroom. Smith apparently had been sick for several days with some kind of stomach flu.

Chief Charlie Tiger of the Seminole Police Department said that there was no evidence to suggest a crime took place, nor were there any illegal drugs at the scene. Tiger did say that prescription drugs were there but did not name what the drugs were.

Smith, the 39-year-old former Playboy Playmate, jeans model, reality TV star and would-be oil heiress who died Thursday after collapsing at a Florida hotel .

The Seminole, Fla., police chief told reporters in a Thursday afternoon news conference that a private nurse employed by Smith made a 911 call at 1:38 p.m. EST after finding Smith unresponsive in her sixth-floor room at the Seminole Hard Rock Hotel and Casino.

Smith's bodyguard performed CPR at 1:45 p.m., and she was rushed by paramedics to nearby Memorial Regional Hospital at just after 2 p.m. Officials said she could not be revived. She was declared dead at a hospital.

The police chief said Smith had checked into the hotel on Monday and was scheduled to check out on Friday.

Later Thursday, two sheriff's deputies carried out at least eight brown paper bags sealed with red evidence tape from Smith's hotel room.

Smith's attorney Ron Rale said claims that her death was drug-related are "nonsense." But a former attorney for Smith in the Bahamas said he thinks it'll turn out that drugs did kill Smith, as they apparently killed her 20-year-old son last September.

Just days before her son died, Smith gave birth to a daughter in the Bahamas. Two men, Smith's partner Howard K. Stern and her ex-boyfriend Larry Birkhead, claim to be the girl's father, and an emergency hearing on the paternity is scheduled for Friday in Los Angeles.

In addition, Zsa Zsa Gabor's husband has stepped foward to claim that he could be the father of Smith's daughter. Prince Frederick Von Anhalt claimed that he had a 10-year affair with Smith, including around the time she got pregnant.

At the time of her death, Smith was still entangled in a dispute with the family of her late husband, oil tycoon J. Howard Marshall. He was 89 when the two married in 1994. A federal court has awarded Smith $474 million from Marshall's estate but his family is fighting it.