Sylvester Stallone is being investigated by police over an allegation that he raped a teenager in the 1990s.

Santa Monica Police Department said on Wednesday that an accuser came forward last month to allege an incident took place in the city two decades ago.

The Rocky actor, 71, has reportedly hit back, accusing the woman of filing a false report against him.

TMZ reported that the star's lawyer, Marty Singer, had denied an allegation of rape against his client, made by a woman who said it took place in the actor's office.

Stallone denies the allegation, the website reports. He admits he had spent 3 days with her during a 1987 movie shoot in Israel.

(Image: Ron Galella Collection)

The actor says he was single, she was not a minor and maintains there was never a rape. He also denies he saw her at all in 1990, TMZ reported.

Stallone had previously issued a denial over reports that a 16-year-old fan had accused him of sexually assaulting her in Las Vegas in the previous decade.

The Santa Monica force's spokesman, Lieutenant Saul Rodriguez, said: "I can confirm we received an allegation of sexual misconduct involving Mr Stallone.

"The (alleged) victim came forward to report the incident in November 2017. The alleged incident occurred in the early 1990s in Santa Monica."

(Image: Getty)

The claim is believed to fall outside California's statute of limitations, which has since been scrapped, but the spokesman said a "thorough investigation" would be made before the case is presented to the district attorney.

Previously, Stallone's spokeswoman Michelle Bega described the Las Vegas allegation as a "ridiculous, categorically false story".

Mail Online had reported that Las Vegas Metropolitan Police Department documents detailed a fan alleging she was assaulted by Stallone and a bodyguard in a hotel room in 1986.

(Image: REX/Shutterstock)

The girl said she was left feeling "humiliated and ashamed" by the event and did not want to prosecute so the force dropped the case, according to the report.

The allegations come as Hollywood continues to reel in the wake of a sexual harassment scandal which has seen ramifications against producer Harvey Weinstein and actors including Louis CK and Kevin Spacey.

Mr Singer is yet to respond to a request for comment over the latest allegation.