Oscar-winning actor Kevin Spacey is being investigated by British police over an alleged sexual assault, according to reports.

It is understood officers from the Met Police's child abuse and sexual offences command are looking into claims the 'House Of Cards' actor sexually assaulted a man in Lambeth, London in 2008.

The Met declined to identify the alleged attacker but said in a statement: "On Wednesday, 1 November, City of London Police referred an allegation of sexual assault to the Metropolitan Police Service.

"It is alleged a man assaulted another man in 2008 in Lambeth.

"Officers from the Child Abuse and Sexual Offences Command are investigating."

City of London Police confirmed they had referred an allegation of sexual assault from 2008 in Lambeth to Scotland Yard.

Mr Spacey is seeking unspecified treatment following allegations of sexual misconduct that have forced a halt in production of his Netflix show 'House of Cards' and a social media backlash.

"Kevin Spacey is taking the time necessary to seek evaluation and treatment," his representatives said in a statement.

No details on the nature of the treatment were provided to an email from Reuters seeking further comment.

Yesterday, CNN published a report in which eight current and former employees of 'House of Cards,' who were not identified, alleged sexual misconduct against Mr Spacey.

'House of Cards' production company, Media Rights Capital, said in an emailed statement to Reuters on Thursday that it was "deeply troubled to learn about these new allegations."

The company said in the statement that it had handled one incident in 2012 in which a crew member it did not identify had "shared a complaint about a specific remark and gesture made by Kevin Spacey" and that immediate action had been taken and the issue was resolved.

It said Mr Spacey had "willingly participated in a training process" and that it was not aware of any complaints since then involving the actor.

Netflix said in an emailed statement that it was aware of the 2012 incident involving Mr Spacey and "is not aware of any other incidents involving Kevin Spacey on-set."

Netflix said earlier this week that it was "deeply troubled" by Anthony Rapp's allegation and suspended production of the upcoming sixth and final season of 'House of Cards,' in which Mr Spacey plays US President Frank Underwood.

Reuters was unable to independently confirm any of the accusations.

Media Rights Capital said that it had installed an anonymous complaint hotline, crisis counselors and sexual harassment legal advisors for the 'House of Cards' crew this week, and would "continue to thoroughly investigate all current claims and any new claims that are formally brought to our attention."

Over the weekend Mr Spacey apologised to Mr Rapp, who had accused him of trying to seduce him in 1986 when Mr Rapp was 14.

As part of his apology, Mr Spacey announced he was gay but angered many in the LGBT community and beyond who saw his announcement as an effort to divert attention from the accusation by Mr Rapp.

Mr Rapp has said on his Twitter feed that he would have no further comment.

Mr Spacey's announcement follows harassment allegations against him this week by Mexican actor Roberto Cavazos, who worked in the London theatre where Mr Spacey was artistic director from 2004-2015, and US filmmaker Tony Montana.