BOULDER CITY, Nev. (AP) — Coroner’s officials in Las Vegas say toxicology tests results could take weeks in the investigation of a 48-year-old Utah scuba diving instructor’s death during the weekend at Lake Mead.

National Park Service spokeswoman Christie Vanover says Xavier Fleuranceau of Santaquin, Utah, was with three other people at a depth of 350 feet in the Black Canyon area on Saturday when he ran out of air.

Fleuranceau’s dive partner shared a spare air tank as the two began to ascend before Fleuranceau separated from a safety line.

He performed a free ascent without gas while the other divers ascended using normal decompression.

Fleuranceau was found face-down in the water and paramedics declared him dead at 1:46 p.m.

Vanover says Park Service investigators are checking the dive equipment for malfunctions.

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