A search and rescue operation has turned into a recovery effort for Naya Rivera.
The Glee alum has been missing since Wednesday after swimming at Lake Piru in California.
"We’re presuming that an accident happened and we’re presuming she drowned in the lake,” Deputy Chris Dyer said at a news conference Thursday afternoon.
“The goal is still to bring Miss Rivera home to her family,” he said.
Footage of Rivera's possible last moments alive were also released by the Ventura County Sheriff's Department.
The footage shows the 33-year-old and her four-year-old son, Josey, arriving as they rent a boat.
Around 100 volunteers and safety personnel from the Ventura County Sheriff's Office and the U.S. Coast Guard were joined by specialized dive teams from Los Angeles, San Luis Obispo, and Tulare counties, were involved in the search for the actress.
An initial search operation was called off on Wednesday at nightfall, but resumed Thursday morning.
The visibility of the lake is a big issue plaguing people working on the recovery operation.
“There’s a lot of challenges in a reservoir this size, at times with visibility,” Ventura County Sheriff's Department Captain Eric Buschow told the Los Angeles Times Thursday.
“I don’t have details yet as to the depth of the area where the boat was found or what conditions they’re encountering out there.”
While the search for Rivera continues, locals have hit out at the lack of protection for swimmers whose lives are at risk on the lake, according to TMZ.
More than 12,000 people have signed a petition demanding more effective warnings for swimmers who are unaware that the waters below are perilous.
The outlet states that the visibility of the water was between 5 to 9 inches at the time Rivera jumped in.
The lake is saddled with strong currents, and the bottom is filled with trees and other debris, meaning that swimmers can easily get entangled.
The petition reads, "People have been asking for years for the city to put up warning signs for swimmers. Locals of Ventura County don’t go to Lake Piru for this reason! Tourists have no idea what they’re getting into. Lake Piru needs signs. We’re tired of waiting. We need justice for all those who got lost at Lake Piru. Put up the signs."
Rivera is best known for her role as Santana Lopez on FOX's Glee, a role she held from the show's debut to its 2015 finale.
More recently, she appeared on Step Up: High Water, which was recently picked up for a third season at Starz after Youtube canceled it.
Paul Dailly is the Associate Editor for TV Fanatic. Follow him on Twitter.