Sonar equipment and a specially-trained dog are being used to search for "Glee" actress Naya Rivera in murky California waters.
According to CNN, Ventura County authorities say the recovery operation could take days.
Rivera, 33, went to Lake Piru on Wednesday.
She rented a pontoon boat with her 4-year-old son, then vanished.
Rivera's son was on the boat, but she was nowhere to be found.
