Sylvester Stallone was accused of sexual assault by a 16-year-old girl while he was filming a movie in Las Vegas in the late 1980s, according to a bombshell police report obtained by DailyMail.com.

The Rocky actor was 40 years old when an unnamed teenager disclosed to Las Vegas police that she had been 'intimidated' into having sex with him and his bodyguard Michael 'Mike' De Luca at the former Las Vegas Hilton hotel in July 1986.

The 16-year-old claimed she had sex with Stallone and he encouraged De Luca to join them. At that point she became 'very uncomfortable' with the encounter but felt she had 'no choice'.

De Luca then forced the teenager to perform oral sex on him before penetrating her, while Stallone made her give him oral sex, according to the police report.

Retired Las Vegas metro police department detective sergeant John Samolovitch, who was head of the sexual assault unit at the time, confirmed to DailyMail.com ‘the copy of the police report is in fact a true copy of the original report.’

Michelle Bega, spokeswoman for Stallone, told DailyMail.com: 'This is a ridiculous, categorically false story. No one was ever aware of this story until it was published today, including Mr. Stallone. At no time was Mr. Stallone ever contacted by any authorities or anyone else regarding this matter.'

After the incident, the teen claims Stallone threatened her - she couldn't tell anyone because both men were married and if she said anything, 'they would have to beat her head in', before laughing with De Luca.

The unidentified teen ultimately decided not to pursue charges against either men because she was 'humiliated and ashamed', as well as being 'scared', according to the police report.

Sylvester Stallone, 71, was accused of sexually assaulting a 16-year-old fan girl when he was 40 years old while he was filming Over the Top in Las Vegas in 1986

Stallone allegedly had sex with the girl, telling her she was 'very tight'. Stallone's bodyguard Michael 'Mike' De Luca then 'forced' her to give him a blowjob before penetrating her while Stallone received oral sex from the teen, according to a police report. Pictured: Stallone and De Luca in 1987

The teen claims Stallone said she couldn't tell anyone because both men were married and if she said anything, 'they would have to beat her head in', before laughing with De Luca. The alleged incident took place at the Las Vegas Hilton hotel (pictured)

At the time of the incident Stallone, now 71, was 40 years old. Bodyguard De Luca, who was shot and killed by California police during a traffic stop in 2013, was 27 years old at the time.

Police were alerted to the incident when a hotel employee called police to report that a friend of the victim said she needed advice on the matter.

When officials tracked down the teen, she relayed details of the alleged assault to them.

She said she was staying at the Las Vegas Hilton hotel with family friends for 10 days, from July 18 to July 28, during the time that Stallone happened to be filming at the hotel for the upcoming movie Over the Top.

The teen said she met actor David Mendenhall, who was playing Stallone's son in the film, at the hotel's arcade and he introduced her and her cousin to Stallone on Wednesday, July 23, 1986.

In the following days, the cast and crew of the movie continued filming at the hotel, and on Friday, the teen said she saw Stallone and got his autograph.

According to the police report, Stallone asked the girl how old she was and after learning she was 16 years old, he asked her 'how she got such a build'.

One of the teen's friends had received a kiss on the cheek from Stallone during the conversation, so the teen said she also asked for a peck on the cheek from Stallone.

The teen said she met actor David Mendenhall, who was playing Stallone's son in the film, at the hotel's arcade, and he introduced her and her cousin to Stallone on Wednesday, July 23, 1986. Pictured: Stallone and Mendenhall on set of the movie Over the Top

The girl told police that De Luca gave her keys to Stallone's hotel room on the 27th floor, where she claims she had sex with Stallone. According to police, when De Luca became involved 'she became very uncomfortable with the situation.' She 'did not want to have any type of sexual contact with the body guard, but felt she had no choice in the matter'. Pictured: A suite at the hotel

'He replied that he would give her a kiss at a later date, that she would not forget', according to the police report.

The next day the teen said she returned to the area in the hotel where the crew was filming with a larger picture for Stallone to autograph for her so that she could give it to a friend.

There, she met De Luca, Stallone's bodyguard, who allegedly asked the teen if Stallone made a pass at her, what would she do.

The teen said she responded that she 'would probably make a pass back at him'.

De Luca then gave her two keys for a room on the 27th floor and told her to go up to the room as soon as possible,' according to the police report.

That night, the teen claims she went up to the 27th floor where she met Stallone and De Luca in the hallway and together, they all went into the hotel suite.

From there, the teen said she and Stallone went into the bedroom, got undressed and began having intercourse, while De Luca stayed in the bathroom.

The teen told police that they 'really didn't have sex' because Stallone only inserted himself 'a little ways' into her and 'only kept it in for a few seconds'.

Stallone remarked to the girl that she was 'very tight' before asking her if she ever had sex with two men at the same time, according to the report.

Neither of the men climaxed but the teen said Stallone asked her if she 'wanted to see come' and then he ejaculated in front of her, the report said. Pictured: Stallone and De Luca

The teen told police that 'Stallone made the comment that they were both married men and that she could not tell anybody about the incident and if she did, that they would have to beat her head in'. Pictured: Stallone with his then wife Brigitte Nielsen in 1987

She said she responded that she hadn't and then Stallone went into the bathroom and brought De Luca into the bedroom.

Stallone allegedly asked De Luca if he wanted a 'blow job' from the teen and De Luca then 'forced her head down onto his penis', according to the police report.

The minor claims De Luca forced her to perform oral sex on him for a few minutes before he 'came around and had vaginal sex with her'.

Then Stallone allegedly 'came over to her and pushed her head down onto his penis and made her give him a blow job'.

Neither of the men climaxed but the teen said that Stallone asked her if she 'wanted to see come' and then he ejaculated in front of her, the report continued.

The teen told police that after she got dressed, 'Stallone made the comment that they were both married men and that she could not tell anybody about the incident and if she did, that they would have to beat her head in'.

Stallone and De Luca both 'laughed after he made the comment', according to the report.

Police noted that 'during the interview [the teen] became emotionally upset numerous times, crying and sobbing.'

At the time of the incident, Stallone, now 71, was 40 years old. Bodyguard De Luca, who was shot and killed by California police during a traffic stop in 2013, was 27. Pictured: Stallone and De Luca in 1987

Police noted the teen had 'difficulty in relating her thoughts'. When pressed if she wanted to pursue charges against the men, she said: 'I'm humiliated and ashamed, but I don't want to prosecute. I'm kind of scared and I'm very ashamed'

The report continued: 'She indicated that if the sexual encounter had only been with Stallone, she would not pursue this matter, but due to the fact that Mike, the bodyguard became involved in the sexual incident, she didn't know what she wanted to do.'

According to police, when De Luca became involved in the sexual encounter 'she became very uncomfortable with the situation. She states she did not want to have any type of sexual contact with the bodyguard, but felt she had no choice in the matter.

'She states there was no actual physical force, but she did feel intimidated.'

Police noted in their report that the teen had 'difficulty in relating her thoughts' and was 'extremely emotional' when telling her story.

When pressed if she wanted to pursue charges against Stallone and De Luca, the girl told police: 'I'm humiliated and ashamed, but I don't want to prosecute.

'I'm kind of scared and I'm very ashamed. I don't want anybody else to have that happen to them, but I don't want to prosecute. I cannot talk about this anymore, please leave me alone.'

She later signed a no prosecution form and the matter was dropped, although police did confiscate De Luca's concealed weapon permit on July 30, 1986.

A story about Sly Stallone being involved in a possible sexual assault in Las Vegas in 1986 was first reported by Doug Poppa of the Baltimore Post Examiner.

The bombshell police report was made a year before Stallone's half-sister Toni-Ann Filiti, threatened him with a lawsuit in 1987, alleging that Stallone raped her and sexually assaulted her. Pictured: Stallone, De Luca and Nielsen in August 1986

The bombshell police report was made a year before Stallone's half-sister Toni-Ann Filiti, threatened him with a lawsuit in 1987, alleging that Stallone raped her and sexually assaulted her for years.

Although court documents show the actor 'vigorously denied and continues to deny and dispute all claims of wrongdoing', he agreed to give Filiti a lump sum of $2 million, as well as $16,666 a month for the rest of her life.

His half-sister, whose own mother claimed she was a drug addict, died in 2012 after a battle with lung cancer.

Stallone is one of the most recent A-listers in Hollywood to be accused of sexual assault and/or harassment in the wake of damaging claims made against Harvey Weinstein, Kevin Spacey, Louis C.K., Brett Ratner, among several others.