Former Glee actress Naya Rivera has gone missing at a lake in Southern California, the Ventura County Sheriff's Department said.
A search operation was launched after her four-year-old son was reportedly found alone on a rented boat at Lake Piru.
The search will resume "at first light" on Thursday, the sheriff's department said.
Rivera, 33, is best known for playing Santana Lopez on musical comedy series Glee.
According to local reports quoting the sheriff's department, Nivera rented a boat at Lake Piru at about 1pm local time.
The alarm was raised and a search operation launched using helicopters, drones and dive teams, police said.
On Tuesday, Rivera tweeted a picture of her and the boy together, which was captioned: "Just the two of us."