Britain's late Princess Diana once leapt 20 feet off her hotel balcony to escape prying eyes during a night-time escapade at an Austrian ski resort, a former police bodyguard revealed on Sunday.

Ken Wharfe, in a book being serialized by Britain's Sunday Times newspaper, said he personally verified Diana's dangerous method of escape on the March 1993, skiing trip.

"Directly beneath her balcony I found a perfect impression of the princess's body in the deep snow. Footprints led away into the town," he said in the extract from "Diana: Closely Guarded Secret."

Later, Diana, who was being hunted by paparazzi while on holiday trying to escape the trauma of her ruined marriage with Prince Charles, tried to justify her rashness.

"Ken, I just needed some air," he quoted her as saying. "Yes, I did jump from the balcony. I knew it was okay -- it was deep, soft snow, and I knew it would be all right."

The extracts of the book by Wharfe, who shadowed Diana for nearly six years between 1988 to 1993 as her personal protection officer, were the latest revelations to fuel Britons' endless fascination with the former princess.

Diana died five years ago in a car crash in Paris.

Wharfe, in a highly sympathetic portrayal of Diana, also recalled "an even more worrying pisode" in 1992 when Diana disappeared on a yacht she was sharing with Charles and guests.

"There was a real fear that she had jumped overboard. She was not in her cabin, and nobody had the least idea where she might be. Panic set in," Wharfe wrote.

"I then remembered that Diana had spent some time by the lifeboats, and went to investigate. In one, crouched beneath the canvas cover in floods of tears, I found the princess. She had been sitting there for two hours, sobbing."

The bodyguard then chatted with her for two hours under the cover, listening to Diana's complaints about "the Rottweiler" -- her name for Charles' lover Camilla Parker Bowles.

In other extracts, Wharfe describes how he provided security for Diana during her liaisons with different boyfriends, and how she once discovered Charles and Parker Bowles hidden away together during a society party.

"We went to the nursery or some room in the basement and there we found the prince and Camilla, sat there talking," he said. "I think that was really the turning point. It was confirmation of what she (Diana) didn't want to believe."