Police in California have confirmed that the body found in Lake Piru is that of missing Glee actress Naya Rivera. 

The 33-year-old disappeared while on a boating trip with her four-year-old son at Lake Piru last Wednesday.

A rescue mission was launched, but less than 24 hours later police said Rivera, best known for playing a high school cheerleader on musical comedy series Glee, was presumed dead.

Rivera (right) pictured with Glee co-star Lea Michele 

Rivera drowned at Lake Piru, which is a popular spot for swimmers about 56 miles north-west of central Los Angeles.

Her son, Josey Hollis Dorsey, was found asleep and wearing a life jacket on the boat, with his mother nowhere to be seen.

He told authorities that they went swimming and his mother never got back on the boat.

During a press conference on Monday to announce the actress’s death, the authorities said that they are working with the assumption that the boat drifted away in the lake's current.

The police also believe that Naya used all of her energy to put her son back in the boat and she didn’t have enough energy to save herself.

Naya Rivera and son
Naya Rivera with her son Josey Hollis Dorsey

Ventura County Sheriff Bill Ayub said: "It would be speculation to say at this point. There are a lot of currents on the lake that appear particularly in the afternoon.

"We believe it was mid-afternoon when she disappeared, the idea perhaps being that the boat started drifting, it was unanchored, and that she mustered enough energy to get her son back onto the boat, but not enough to save herself."

Ayub also said there is no sign of foul play and no indication that this was a suicide.

Naya Rivera and Ryan Dorsey
Naya Rivera was married to Ryan Dorsey from 2014 - 2018

Shortly before the press conference took place, Glee cast members visited the lake and held hands on the shore during a vigil for Naya.

CCTV from the dock shows her rented boat departing at about 1pm, on Wednesday July 9, and it was later found drifting in the northern area of the lake at about 4pm.

Naya Rivera in Glee
Naya Rivera (L) as high school cheerleader Santana in Glee

Investigators had stressed the many difficulties posed by the search, including strong currents, dangerous underwater debris and visibility of 1ft-2ft. 

Rivera was married to Ryan Dorsey from 2014 to 2018. She is survived by her son, her parents and her younger brother and sister.