A spokesperson for the Los Angeles Police Department told the BBC that the 31-year-old was safe. They would not provide further details.
A statement said Tanya’s family were “relieved and extremely grateful”.
A tweet from the FindTanyaFear Twitter account, which is run by her family, said: “It is with great pleasure and relief to report that Tanya has been found safe by police today.
“We understand she is not physically harmed but as a precaution, is being assessed at a local hospital.
“We wish to thank police, members of the public for their efforts in locating Tanya, as well as the outpouring of concern and support over the last several days.
“Tanya’s family are relieved and extremely grateful”.
A statement posted on the Twitter account earlier on Monday said she left without her mobile phone or purse and was reported missing by a friend.
Her mother, Yvonne Marimo, said at the time: “I am devastated about this situation, and I appeal to anyone with information to please come forward to bring our daughter back home safely”.
As well as appearing in Doctor Who as Dr Jade McIntyre alongside Jodie Whittaker in 2018, Tanya has also had roles in Endeavour, DCI Banks, Cleaning Up and Spotless.
She also appeared in the movie Kick-Ass 2 and had recently started doing stand-up comedy after arriving in Los Angeles two months ago.