A 22-year-old woman has gone missing after falling from a jet ski on Lake Mead.

A 22-year-old woman has gone missing after she and a man fell off a jet ski in Lake Mead this week, park officials said.

Around 6:15 a.m. Thursday, the National Park Service was alerted that two people had fallen into a lake near the Boulder Islands.

None of them were wearing a life jacket, the park said.

Park rangers and search and rescue teams from the Las Vegas Metropolitan Police Department found the man on Thursday.

On Friday, the woman was still missing and “has not been seen since she entered the water,” the park service said.

She was identified only as Lily, a resident of Boulder City, Nevada.

Lily was described as being 5’2″ and weighing between 110 and 120 pounds, with red-dyed brown hair. She was last seen wearing black yoga pants and a white shirt, and has a captain’s helm tattoo on her left forearm.

The investigation is carried out by rangers and special agents of the investigative department of the park service.