Police searching for missing Glee actress Naya Rivera say a body has been found in the lake in southern California where she and her son went out on a boat.

Rivera, 33, went missing last Wednesday when out with her four-year-old son Josey on Lake Piru. He was found alone and asleep in a boat.

Divers and teams using sonar equipment resumed the search on Monday. Police have not given details, and a news conference will be held later.

Her son told police they had gone swimming but the actress never returned. After a massive search and rescue operation found no trace of Rivera, police moved to a "search and recovery operation".

Authorities are yet to formally confirm that the body is that of the actress. They announced the grim discovery on Twitter, saying: 'A body has been found at Lake Piru this morning.