"We are confident the body we found is that of Naya Rivera," Ventura County Sheriff Bill Ayub said in a news conference. "It has been an extremely difficult time for her family throughout this ordeal ... our hearts are with them and we share in their grief for Naya’s loss."
Ayub said Rivera's 4-year-old son, Josey Dorsey, told investigators that they swam in the lake together and "he looked back and saw her disappear under the surface of the water" after she helped him onto their rented pontoon boat.
"We believe that she mustered enough energy to get her son back on the boat, but not enough to save herself," Ayub later added.
Presley Ann/Getty Images Naya Rivera
In the wake of the tragic news, fans have begun circulating a clip of Rivera's cover of "If I Die Young" by the The Band Perry, which she performed in Glee's tribute episode following Monteith's death.
Monteith was 31 when he died of a heroin overdose on July 13, 2013.
"Today marks the 7th anniversary of Cory Monteith’s death. You broke down while singing this for him, now we’re the ones breaking down singing it for you," one fan wrote on Twitter. "You’ll forever live on in our hearts, Naya Rivera.❤️"
"Naya Rivera singing 'If I Die Young... sink in me in the river...' as tribute to Cory and then her body being found on the exact anniversary of his death is just wow...so heartbreaking 😔 💔," another tweeted.
A third fan wrote, "Hearing Naya Rivera sing If I Die Young for Cory Monteith and now they're both in heaven 💔."
Today marks the 7th anniversary of Cory Monteith’s death. You broke down while singing this for him, now we’re the ones breaking down singing it for you. You’ll forever live on in our hearts, Naya Rivera.❤️pic.twitter.com/toTYF9yuRN— TEAM SPEARS (@wetbritney) July 13, 2020
Rivera played Santana Lopez, a cheerleader and star glee club member, on the musical comedy Glee. She appeared in nearly every episode of hit show's six-season run and was considered a trailblazer for LGBTQ characters. Santana came out in the 2011 episode "I Kissed a Girl" after developing feelings for best friend Brittany Pierce (Heather Morris).
Meanwhile, Monteith played high school football star Finn Hudson on the Fox series until his death in 2013. His character was written out of the show's fifth season, with no cause of death given.
Rivera's former Glee castmates have been mourning the actress on social media.
FOX Image Collection via Getty Naya Rivera and Cory Monteith on Glee
"Rest sweet, Naya. What a force you were," tweeted Jane Lynch, who played cheerleading coach Sue Sylvester on the show. "Love and peace to your family."
Chris Colfer, who played Kurt Hummel, posted a lengthy and poignant caption alongside an Instagram photo of the pair.
"How can you convey all your love and respect for someone in one post? How can you summarize a decade of friendship and laughter with words alone?" he wrote. "If you were friends with Naya Rivera, you simply can’t. Her brilliance and humor were unmatched. Her beauty and talent were otherworldly. She spoke truth to power with poise and fearlessness. She could turn a bad day into a great day with a single remark. She inspired and uplifted people without even trying. Being close to her was both a badge of honor and a suit of armor. Naya was truly one of a kind, and she always will be. 💔 Sending all my love to her wonderful family and her beautiful son."