Kevin Spacey is being investigated by police for a sexual assault allegation

British police are investigating an allegation of sexual assault made against Kevin Spacey.

An alleged victim claimed today that after being invited to Spacey’s London home for a drink in 2008, he passed out – and woke to find the Hollywood star performing oral sex on him.

The man, who was 23 at the time, told the House of Cards star to stop and ran from the house, he claimed in The Sun.

The alleged victim added that Spacey had said to him: “Don’t tell anyone about this.”

“On 1 November, City of London police referred an allegation of sexual assault to the Metropolitan police service,” a police spokesman said today.

“It is alleged a man assaulted another man in 2008 in Lambeth. Officers from the child abuse and sexual offences command are investigating.”

Though police have not confirmed his identity, the alleged perpetrator is believed to be Spacey.

The actor has repeatedly been accused of inappropriate sexual behaviour this week, since Anthony Rapp accused him of making sexual advances on him when he was 14.

On Sunday, Star Trek actor Rapp said that in 1986, a 26-year-old Spacey invited him to a party at his New York apartment and climbed on top of the child, “trying to get with me sexually.”

In an interview with BuzzFeed, Rapp, now 46, said he managed to flee before the encounter progressed any further.

In response, Spacey wrote on Twitter that he didn’t remember the incident, but apologised for “what would have been deeply inappropriate drunken behaviour.”

The Baby Driver actor added that he was “sorry for the feelings he [Rapp] describes having carried with him all these years,” before saying: “I choose now to live as a gay man.”

In a statement, his representatives have said: “Kevin Spacey is taking the time necessary to seek evaluation and treatment.”