The Ghost actress, 52, and her three daughters were not in California when the body of a 21-year-old man was discovered in the water at her Beverly Hills mansion.
It's believed a party had been held at Demi's home while she was away and that the young man drowned – although an official report has not been released yet.
In a statement, Demi admitted she was shocked by the news, saying: "I am in absolute shock. I was out of the country travelling to meet my daughters for a birthday celebration when I got this devastating news."
She added: "The loss of a child is an unthinkable tragedy and my heart goes out to this young man's family and friends," she continued. "I ask that you please respect the privacy of all concerned during this sensitive time."
Police in Los Angeles have identified the deceased man as Edenilson Steven Valle. Early reports suggest he was a member of Demi's household staff. It's been reported Edenilson could not swim.
The Los Angeles County Coronor told BBC News that Edenilson was discovered at the deep end of the pool on Sunday morning after friends noticed he'd been missing or around ten to 15 minutes. He was pronounced dead at the scene.
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