LAKE PIRU (CBSLA/AP) — The 4-year-old son of “Glee” actress Naya Rivera, whose body was recovered Monday from Lake Piru after she went missing during a boating trip with her son last week, says his mom boosted him back on to the deck of their rented boat before he looked back and saw her disappearing under the water, authorities said.

“She must have mustered enough energy to get her son back on the boat, but not enough to save herself,” Ventura County Sheriff Bill Ayub said at a news conference.

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The boy, Josey Hollis Dorsey, was found asleep and alone in a life vest on the drifting pontoon boat about three hours after they launched on Lake Piru northwest of Los Angeles, setting off a six-day search that ended with the discovery of the body of the 33-year-old floating near the surface early Monday, authorities said.

The mother and son had gone swimming, which was permitted in that part of the lake, Ayub said. She was not wearing a life vest, and an adult-sized life vest as found in the boat.

US actress Naya Rivera and son Josey Hollis Dorsey arrive for the premiere of “The Lego Movie 2: The Second Part” at the Regency Village theatre on February 2, 2019 in Westwood, California. (Photo by Chris Delmas / AFP) (Photo by CHRIS DELMAS/AFP via Getty Images)

Authorities believe that Rivera drowned accidentally, and that her body was most likely trapped in the vegetation under the lake for several days before floating to the top, Ayub said.

Crews had been searching the lake exhaustively for Rivera, who went missing at the lake last Wednesday.

Buschow said crews found the body floating in the northeast side of the lake, the area where Rivera was last seen.

According to Ayub, the depth of the water in the area where Rivera had been found is between 35 and 60 feet, and that there can be trees and brush underwater. The area had been searched extensively with sonar and by divers, who described murky conditions underwater that forced them to remain tethered with ropes in order to find their way back to the boats.

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LOS ANGELES, CA – MARCH 18: Actress Naya Rivera attends Fox’s “GLEE” 100th Episode Celebration held at Chateau Marmont on March 18, 2014 in Los Angeles, California. (Photo by Mark Davis/Getty Images)

 

Rivera is presumed to have drowned in the lake. Ayub said there was no indication of foul play or suicide.

The body has been taken to the coroner’s office for an autopsy.

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Rivera isn’t the first “Glee” cast member to meet a tragic end: co-star Cory Monteith was found dead July 13, 2013 – exactly seven years to the day Rivera’s body was recovered – from what investigators later said was a fatal drug overdose.

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