As the search for Naya Rivera continues, police now believe her disappearance was the result of a tragic accident.

The Glee alum went missing Wednesday afternoon (July 8) after police recovered her 4-year-old son, Josey, from the boat Rivera had rented hours prior to going out swimming on Lake Piru in Southern California. As yet, the 33-year-old star remains missing, which sparked speculations insisting she may have taken her own life.

Police officials, however, are ruling out suicide as there is no evidence to suggest this was the case.

“We interviewed her son and there was nothing that we learned from her son that would have suggested that this was suicide. Everything that we’ve learned so far leads to this being some sort of water recreational accident,” Sgt. Kevin Donoghue told PEOPLE.

“To say definitively what actually happened, we really can’t say. We just don’t know, it’s a mystery,” Donoghue added. “We’re still investigating, we’re still searching. We’re trying to uncover clues as we go. But so far, we really don’t have a lot of information to make any guesses as to what could have happened.”

Josey was found alone and sleeping on the boat wearing his life vest, but Rivera was nowhere to be found.

According to reports, Josey told authorities he and his mom were swimming together but only he returned to the boat. (Rivera's wallet, ID, and an adult life vest were on the boat when Josey was found.) What remains unclear, though, is whether Josey got back onto the boat by himself or if his mother assisted him.

“I know she was in the water. I don’t know if she helped him back on the boat. That I don’t know,” Donoghue said.

Since her disappearance, the search for Rivera has shifted from a rescue mission to a recovery mission as the actress has been presumed dead by police.

Right now, the rescue team is having difficulty finding Rivera in Lake Piru, which is said to be filled with trees and debris making it barely visibly the closer divers get to the bottom of the lake. “So if she’s resting at the bottom of the lake,” Donoghue explained, “she’s probably resting somewhere where there’s zero visibility.”

The last known footage of Rivera and her son has since been released in the interim — watch it here.

Photo: Getty Images