Ventura County Sheriff's officials on Thursday said investigators believe "Glee" actress Naya Rivera drowned in "what appears to be a tragic accident."
Authorities were searching a Southern California lake for Rivera, after her 4-year-old son was found alone in a boat she had rented Wednesday. According to officials, the search for the missing actress had turned into a recovery mission.
"We're presuming that an accident happened and we're presuming that she drowned in the lake," Ventura County Sheriff's Deputy Chris Dyer said, adding that there were no signs of foul play, NBC News reported.
Dyer added that it would not change efforts to locate Rivera.
The 33-year-old had been boating with her son on Lake Piru, the Ventura County Sheriff's Department said. Rivera rented a boat around 1 p.m., the department reported, and her son was found napping alone in the vessel three hours later.
Rivera's son said the two had been swimming, but Rivera never returned, according to Capt. Eric Buschow. The boy was wearing a life vest and another adult life vest was found on the boat, he said.
The Ventura County Sheriff's Department said multiple teams of search and rescue personnel are searching Lake Piru for Rivera. More than 80 people are involved in the search, using helicopters, boats, ATV vehicles and ground units to try and locate her.
Additionally, specialized dive teams from Los Angeles County, San Luis Obispo County and Tulare County are also helping in the search.
"Our hearts and prayers go out the all of the family and friends of the Rivera family," the department said.
Rivera is best known for her portrayal of Santana Lopez on "Glee," a show that aired on Fox from 2009 to 2015 and centered around a high school glee club.