A manicurist who worked at Wynn's flagship casino recounted an incident with Wynn in 2005, telling the newspaper that he forced her to have sex in his office. Colleagues recounted her returning to the on-site salon visibly distressed, the report says, and she told others Wynn pressured her to take her clothes off and lie on the massage table kept at his office. Those people she told about the incident recounted to the newspaper that the manicurist did not want to have sex with Wynn, but said he was persistent in his demands.
The WSJ said it contacted over 150 current and former employees. The majority of those who spoke worried that talking to the media would hurt their job opportunities, citing Wynn's vast and powerful influence throughout Nevada and the casino industry.
In a statement, Wynn said that "the idea that I ever assaulted any woman is preposterous."
"We find ourselves in a world where people can make allegations, regardless of the truth, and a person is left with the choice of weathering insulting publicity or engaging in multi-year lawsuits. It is deplorable for anyone to find themselves in this situation," Wynn said in the statement.
He claimed the accusations were stirred up by his ex-wife, Elaine, who he said is seeking a revised settlement of their divorce. "I have repeatedly refused to capitulate to her demands," he added. "In response, I remain focused on Wynn Resorts, our employees and our shareholders and will not be distracted from those efforts."
Wynn, who also acts as finance chairman of the Republican National Committee, would not comment on whether he would relinquish his role with the RNC, the Washington Post reported.
"Neither Mr. Wynn nor the company have any comment on that," a Wynn Resorts spokesperson told the Washington Post.
Wynn Resorts provided the following statement to CNBC:
The recent allegations about Mr. Wynn reflect allegations made in court hearings by Mr. Wynn's ex-wife, Elaine Wynn, in her legal battle with him and the company. It is clear that Mr. Wynn's ex-wife has sought to use a negative public relations campaign to achieve what she has been unable to do in the courtroom: tarnish the reputation of Mr. Wynn in an attempt to pressure a revised divorce settlement from him. It is noteworthy that although Ms. Wynn says she knew about the 2005 allegations involving Mr. Wynn in 2009, she never made them known to the board of directors, of which she was then a member, and she did not raise them until after Mr. Wynn remarried and the shareholders of Wynn Resorts voted not to elect her to the board. Wynn Resorts is committed to operating with the highest ethical standards and maintaining a safe and respectful culture that has made Wynn Resorts the employer of choice for 23,000 employees worldwide. The Company requires all employees to receive annual anti-harassment training and offers an independent hotline that any employee can use anonymously, without fear of retaliation. Since the inception of the company, not one complaint was made to that hotline regarding Mr. Wynn.
In the aftermath of the explosive report, the Massachusetts Gaming Commission announced it would review a $1.13 billion development project set to open in Everett, Massachusetts next year.
The Wynn Boston Harbor project, which aims to transform the site of a former Monsanto chemical plant into a casino, has survived numerous legal battles with neighboring towns. In light of the allegations against Wynn, it may now may face one more.
Massachusetts Gaming Commission provided the following statement to CNBC:
The Commission is now aware of and is taking very seriously the troubling allegations detailed in the Wall Street Journal article. The suitability and integrity of our gaming licensees is of the utmost importance, and ensuring that suitability is an active and ongoing process. Consequently, the MGC's Investigations and Enforcement Bureau will conduct a regulatory review of this matter to determine the appropriate next steps.
A Wynn Resorts spokesperson told CNBC, the company intends to comply fully with the regulatory review process.
"We have been in contact with the Massachusetts Gaming Commission, and will be fully cooperative with any review the commission chooses to undertake," the spokesperson said.
Elaine Wynn and her legal team did not immediately respond to CNBC's request for comment.
Read the full report from The Wall Street Journal here.
--CNBC's Chloe Aiello contributed to this report.
Image copyright Getty Images Image caption Mr Wynn, who is also a Republican official, at the White House
A top Republican Party official and casino mogul is denying a report he assaulted female employees in a decades-long pattern of abuse.
Steve Wynn is accused of harassing massage therapists and forcing one staff member to have sex with him, according to the Wall Street Journal.
"The idea that I ever assaulted any woman is preposterous," Mr Wynn said in a statement on Friday afternoon.
He blamed his ex-wife, who he is fighting in court, for the "slander".
"The instigation of these accusations is the continued work of my ex-wife Elaine Wynn, with whom I am involved in a terrible and nasty lawsuit," the billionaire, turning 76 on Saturday, said in a statement that his public relations team sent to the BBC.
Image copyright Getty Images Image caption Steve Wynn and his ex-wife Elaine in happier times in Las Vegas back in 2007
Following the report, Wynn Resorts' stock price dropped by more than 10%.
Regulators in Massachusetts, where Mr Wynn is building a casino outside Boston, say they are "taking very seriously the troubling allegations", and have launched a review of his actions.
"The suitability and integrity of our gaming licensees is of the utmost importance, and ensuring that suitability is an active and ongoing process," a spokeswoman said in a statement.
A spokesman for Wynn Resorts would not comment on whether Mr Wynn, who has donated millions to political campaigns, planned to continue in his role as finance chairman of the Republican National Committee (RNC).
Image copyright Getty Images Image caption A Wynn casino in Las Vegas bears his signature
The RNC did not immediately respond to a BBC request for comment.
During his campaign for president, Donald Trump described his fellow businessman as "a great friend".
According to the Wall Street Journal, which said it had interviewed dozens of people who worked with Mr Wynn, he is accused of engaging in a pattern of abuse in which he often harassed massage therapists while alone in his private office.
Image copyright Getty Images Image caption US President Donald Trump has called Mr Wynn a 'great friend'
The gambling industry giant paid $7.5m (£5.2m) to one manicurist who alleged she had been forced into sex by Mr Wynn, the paper claims citing court documents.
Female employees would fake appointments in order to avoid seeing him, or enlist others to pretend to be their assistants in order to avoid being alone with him.
Some would even hide in bathrooms or closets if they heard he was coming to their salon, the paper claimed.
Women told the paper they felt intimidated by the presence of one or more German Shepherd dogs in his office, which they said were taught to respond to commands in German.
Steve Wynn is being accused of sexual misconduct by a number of female employees at his Las Vegas hotel and casino.
The Wall Street Journal spoke with 150 people who currently work for Wynn or have in the past, and a number of the women who no longer work at one of the billionaire businessman's properties were incredibly forthcoming in describing the lengths they would allegedly go to in order to avoid being alone with their boss.
Some scheduled fake appointments to make sure they would not be chosen to give Wynn spa treatments, while others went so far as to hide in bathrooms when he came into the salon.
One worker said that she was coerced into performing a sex act on Wynn, 76, with her hand at the end of his massages, adding that Wynn asked at one point if she could use her mouth rather than rubbing his penis to climax when they were done with the session.
That woman refused, but in 2005 another employee was not able to decline Wynn's advances when he ordered her to disrobe and lie on a table so they could have sex.
She reported Wynn and received a $7.5 million settlement, which was revealed by Wynn's ex-wife Elaine in court papers.
It was that court filing which led to the Journal's investigation.
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These guys: Steve Wynn is being accused of sexual misconduct by a number of female employees at his Las Vegas casino (l t r: Roberto Cavalli, Elaine Wynn, Steve Wynn, Melania Trump, Eva Cavalli and Donald Trump in 2006)
Second wife, third marriage: In 2011, Wynn married socialite Andrea Hissom (pair above at Mar-a-Lago over New Year's)
Viva: In a recent court filing, his ex-wife Elaine alleges that a $7.5 million payout was made in 2007 to a manicurist he forced into having sex with him at his Las Vegas property (above)
The masseuse who brought Wynn to climax with her hand said she refused to do the same with her mouth, while also detailing how the casino magnate slowly groomed her over the course of their relationship.
Wynn booked multiple appointments a week with the woman several years ago, and at one point threw his towel off and never wore it again claims the former employee.
Then, he began to rub her legs while she was massaging him, which led to the session when he allegedly asked her to finish by massaging his penis until he had achieved full release.
At the end of every session, the woman said that Wynn paid her $1,000 in cash, regardless of any extra services that may have been provided for the client's added pleasure.
When she told Wynn that his requests made her uncomfortable he stopped requesting her for massages, and she finally told a co-worker.
She said that she did not go into specifics and just told the woman there had been inappropriate behavior.
That woman recalled the conversation, and added that she did not mention to the female employee that Wynn had also stopped requesting her when she balked at his demands for her to rub his genitals.
Shawn Cardinal, a former personal assistant to Elaine, said that in the late 1990s Wynn began contacting her outside work and demanding the two spend time together alone.
'What are you wearing? Why don’t you hang out with me after work?' he would ask according to Cardinal.
'I was not brave enough to say, "How dare you?" I just joked my way out of it and I made sure I was never alone with him.'
Support system: Wynn married his first wife Elaine (pair above in 2005) in 1963, divorced her in 1986, remarried her in 1991 and divorced her once again in 2010
Anchors away: Multiple spa workers said that Wynn (above in 2013 in St Tropez) could sit with his genitals hanging out of his shorts while getting services at the salon, leading some women to hide from him
Chomping at the bit: Wynn (above in 2014) has denied all the allegations being made against him, saying his wife is out to get him
Wynn also paraded around the casino in short shorts and no underwear at time according to several employees, with workers in the spa stating that his genitals would be hanging out and on full display at times.
And he is accused of trying to get intimate with female workers he could not get alone in a room with him by kissing them in what they describe as sudden attacks that came out of nowhere.
Two women who Wynn allegedly demanded kiss him said that he made these requests after they had been working for him for years, though one did also note that she had been sexually harassed multiple times before that incident.
Sweet treat: Wynn and Andrea in St Tropez in 2014 (above)
That woman said Wynn once ribbed his partially exposed genitals while detailing what sex acts he wished to perform on her and another time called and asked: 'So when are you going to come into my office and f*** me?'
'The idea that I ever assaulted any woman is preposterous,' said Wynn in a statement.
'We find ourselves in a world where people can make allegations, regardless of the truth, and a person is left with the choice of weathering insulting publicity or engaging in multi-year lawsuits. It is deplorable for anyone to find themselves in this situation.'
He then accused his ex-wife of spreading false reports because of the 'terrible and nasty lawsuit' she has filed in hopes of getting a 'revised divorce settlement.'
Elaine is trying to get more control over the $1.9 billion in stock she received after the pair split, while her ex is trying to keep the strong restrictions detailing what she can and cannot do with that money in place.
She wrote in her court filing that it was in 2009 when she learned of the incident involving Wynn and the manicurist, which possible led to their second divorce the following year.
Her argument is that by not telling his board about the payout, Wynn put the company at jeopardy.
That argument is problematic however given that Elaine never said anything during the five years she was on the board after learning about the lawsuit.
There they are: The Wynns attend the Senate policey luncheon at the White House on June 27 (above)
They're back: The Wynns in the East Room of the White House exactly a month later in July (above)
Wynn is the most famous, and successful, casino owner in the world, having been behind countless properties in Las Vegas and Atlantic City including the Golden Nugget, the Mirage, the Bellagio, Treasure island and now the Encore and Wynn resorts an casinos.
He is also an avid art collector and owns or has owned works by Picasso, Vermeer, Rembrandt, Monet, Jeff Koons.
In 2006, he famously put his elbow through Picasso's La Reve while showing it to friends, just before he was set to sell it to hedge fund manager Steven Cohen for a then record-breaking $139 million.
The sale was cancelled when the story of what happened broke, and the painting was repaired at a cost of $90,000. Wynn also later sued his insurance company for failing to pay out what he claims should have been a $54million claim for lost value after he damaged the painting.
Wynn married his first wife Elaine in 1963, divorced her in 1986, remarried her in 1991 and divorced her once again in 2010, with Elaine remaining on the board of his company until 2015.
The two are still locked in a contentious court battle however, with Elaine, 73, filing papers last month asking that her husband give her access to more than $900million worth of stock she received in their divorce.
Elaine, who is worth $1.9billion, said she had handed the shares over to her husband to control after she was awarded them in the divorce 'to help her partner of 41 years and the father of her children.'
The couple has two daughters, Kevyn and Gillian. Keyn was kidnapped in 1993 when she was 27 years old and Wynn paid $1.45million in cash from the casino vault for her safe return.
Police were later able to apprehend the kidnappers as one tried to purchase a Ferrari.
In 2011, Wynn married socialite Andrea Hissom, 54, the mother of model and singer Nick Hissom.
The pair are incredibly close with President Trump and the First Lady, and rang in the New Year at Mar-a-Lago, where Hissom wore a $13,000 Gucci dress
