"Officers from the Child Abuse and Sexual Offences Command are investigating", Scotland Yard said to THR.
The date of the allegation dates back to 2005 and took place in the London borough of Lambeth, the location of the Old Vic theater where Spacey was artistic director.
Last Vic, Old Vic Theater reported that it has received 20 personal testimonies against Kevin Spacey for "misconduct".
A two-time Academy Award victor, Spacey was artistic director of London's Old Vic Theatre between 2004 and 2015.
But it said the same man was accused November 1 of another assault in 2008, also in Lambeth.
"The Old Vic apologizes wholeheartedly to the people who told us that they have been affected", said Varah.
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The craft was navigating normally, underwater, at a speed of five knots toward Mar del Plata when it was last heard from, he said. More than a dozen boats and aircraft from Argentina, the United States, Britain, Chile and Brazil have joined the search effort.
"It is alleged a man assaulted another man (Victim 1) in 2008 in Lambeth", the force said in a statement.
In response to the claims, Spacey issued a post on Twitter in which he wrote that he did not remember the alleged incident and also announced he is living as a gay man.
Current artistic director Matthew Warchus said: "These allegations have been a shock and a disturbing surprise to many of us".
The scandal surrounding the actor began after claims were made by actor Anthony Rapp on October 30 that Mr.
The alleged victim is believed to be an aspiring actor who sought career advice from the House of Cards star. He has denied allegations of assault, but said he is now seeking "evaluation and treatment" of his behavior.
Alleged victim, Daniel Beal said that Spacey showed him his penis in public when he was 19, before giving him his £5,000 watch to buy his silence.