Divers are having to use "touch" to search underwater for Naya Rivera, due to poor visibility in the water.
The 33-year-old actress is presumed dead after she went missing on Wednesday (July 8) afternoon when her four-year-old son Josey was found alone on a boat on Lake Piru in California, and the incident has now been classed as a "recovery operation".
Divers have been searching underwater for the former Glee star's body, but have been having difficulty seeing through the "tree branches and overgrowth" that have fallen into the lake.
Volunteer diver, Max O'Brien said: "The visibility is about 1 to 2 feet (0.3m-0.6m) ... There's a lot of tree branches and overgrowth from when the lake was lower, so we're digging through, breaking through sticks and searching a heavy brush bottom.
"Under the water, it's a lot by feel. Again, there's a lot of shrubbery and sticks that we have to break through as we're going through, so it's kind of a Braille search."
The news comes after Ventura County Sheriff Sergeant Kevin Donoghue admitted there is "no way to really say" what happened to Naya, and said her body "may never come back up".
He explained: "If the body is entangled on something beneath the water, it may never come back up.
"There's no way to really say. We're putting our best foot forward to try and locate her, we're using all the assets that are available to us including technology like sonar."
But he insisted the police are doing "everything [they] can" to find the actress.
He added: "We're relying on their expertise to help us in that endeavour. We're going to do everything that we can to find her."
More than 80 people are involved in the search after the police deployed "helicopters, boats, and ATV vehicles", and it was recently stated in a police report that investigators "believe Naya drowned in what appears to be a tragic accident".— BANG