Crews were searching for Rivera, 33, in Lake Piru, which is approximately 56 miles northwest of downtown Los Angeles.
“There’s no evidence of foul play at this point,” Cpt. Eric Buschow, Ventura County Sheriff’s Office, told KTLA. “This may well be a case of drowning.”
KTLA reported that Rivera rented a boat at the Lake Piru reservoir around 1 p.m. Wednesday.
About three hours later, other boaters found Rivera’s son asleep on the boat and called for help. The boy was wearing a life jacket. He was placed in the custody of family members, KTLA reported.
According to investigators, the boy said he had been swimming with his mother. He was able to climb back into the boat, but she never did. An adult life jacket was found on the boat.
Dive operations were suspended after nightfall and are expected to resume Thursday morning.
On Monday, Rivera posted a picture to social media that appeared to show her kissing her son with the caption “Just the two of us.”
Rivera played Santana, a cheerleader in the musical-comedy “Glee” that aired on Fox from 2009 until 2015. Rivera appeared in 113 episodes of the series and dated co-star Mark Salling, who killed himself in 2018 after pleading guilty to child pornography charges.
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