Body Found in Lake Piru, Where Naya Rivera Went Missing: Police

Five days after Naya Rivera went missing during a visit to Lake Piru with her 4-year-old son, a body has been found at the site.

"A body has been found at Lake Piru this morning," the Ventura County Sheriff's Office tweeted on Monday. "The recovery is in progress."

A news conference is set to take place at 2 p.m. PT at the lake.

On July 8, the former Glee star's son Josey was found alone on a pontoon boat at the Southern California lake, where the pair had been swimming. A day later, authorities announced that Rivera, 33, was presumed dead.

Authorities said Josey was "in good health" despite his mother's disappearance, and the boy was reunited with his father, Rivera's ex-husband Ryan Dorsey. The toddler told investigators that his mother never got back into the boat after they had been in the water.

A source told PEOPLE last week that Rivera's loved ones were in "disbelief."

"Nobody has heard anything," the source said. "Everybody is in a wait-and-see pattern and trying to figure out exactly what happened."

On Sunday, Sgt. Shannon King confirmed to PEOPLE that investigators would be continuing to search for Rivera in the area "at least through Tuesday."

"There's no talk of either one way or the other after Tuesday," King said. "Tuesday's sort of the projected date that we're discussing, and we're going to continue doing what we have been doing."