Medical personnel applied CPR and other lifesaving measures on Anna Nicole Smith's son Daniel for 22 minutes before he was pronounced dead, the head of the hospital said Tuesday. But there was no official word on what caused the death.

Police say the reality TV star and former Playboy playmate found Daniel Smith, 20, unresponsive Sunday morning in a chair in her hospital room, where she was recuperating from giving birth to a baby girl three days earlier, and called for help.

Police said they had no evidence that Daniel Smith had suffered a heart attack or that drugs were involved.

"Resuscitative efforts using advanced life-support protocol continued for 22 minutes without response," said Barry Rassin, president and CEO of Doctors Hospital in Nassau, at a news conference.

Daniel Smith, 20, had arrived at the hospital late Saturday to visit his mother, and Rassin said hospital employees saw him "attending to his mother's comfort" during the night.

Dr. Hubert Minnis, obstetrician for 38-year-old Anna Nicole Smith, said she had an "uneventful" Caesarean section at the private hospital on Thursday.

"Both mother and baby are presently doing well," Minnis said at the press conference.

Police said they were waiting for a pathologist's report to determine the cause of death.

"We have got to give them to time to do their job professionally and properly. I wait for them," said Reginald Ferguson, assistant commissioner of the Royal Bahamian Police Force.

It was unclear whether a coroner had completed the autopsy, or if police would release the results.

"If the family requests that the information not be given out, then certainly, I imagine we would do as they ask," Ferguson said.

Butler's Funeral Homes & Crematoriums, hired by the family, said Tuesday it expected to receive Smith's body after the autopsy is completed and would then submit paperwork for its repatriation to California.

The body was identified at the morgue Monday by Smith's lawyer, Howard K. Stern, who is also handling arrangements with the funeral home, said Loretta Butler-Turner of the funeral home.

When Daniel Smith was born in 1986, his mother was married to Billy Smith. The couple, who met while working together at Jim's Krispy Fried Chicken in Mexia, Texas, married in 1985 and divorced in 1987. The son had small roles in her movies "Skyscraper" and "To the Limit."

The identity of the newborn girl's father has not been publicly disclosed.

Anna Nicole Smith married Texas oil tycoon J. Howard Marshall II in 1994, when she was 26 and he was 89. He died the following year.

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She then feuded with Marshall's son, Pierce Marshall, over her entitlement to the tycoon's estate before he died in June at age 67.

Smith won a US$474 million (euro372 million at current exchange rates) judgment, which was cut to about $89 million (euro70 million), and eventually reduced to zero. In May, the U.S. Supreme Court ruled that the Smith could continue to pursue her claim in federal courts in California, despite a Texas state court ruling that Marshall's youngest son was the sole heir.