The UK's football regulator is in contact with West Ham after allegations were made against co-owner David Sullivan that he had pressured aspiring models for sex.
The 77-year-old recently quit as chairman of the east London football club to fight what he claimed were "false allegations" about his conduct.
On Monday, the BBC and The Times reported the accounts of seven women who claimed Mr. Sullivan engaged in sexually exploitative and predatory behaviour.
The Independent Football Regulator (IFR) said it is in contact with the football club seeking information about Mr. Sullivan's suitability as a co-owner following the claims, which he denies.
An IFR spokesperson said: "These are extremely serious allegations.
"We are in contact with West Ham on this matter and will use our statutory powers to seek urgent information from David Sullivan relating to his suitability under our owners, directors and senior executives regime.
"We are unable to comment further at this stage."
The accounts from the women date back to the 1980s and 1990s, when he owned tabloid newspapers the Daily Sport and the Sunday Sport.
According to the reporting, the claims about Mr. Sullivan involve him pressuring young or aspiring models in their late teens or early 20s.
The Times said it was a two-year investigation, which involved its reporters interviewing dozens of former models and other industry sources.
In a statement, a Department for Culture, Media and Sport spokesman said: "These deeply concerning allegations must be treated with the utmost seriousness and be investigated by the relevant authorities, with victims given the support they need.
"The Government stands strongly against any form of harassment or abuse of power in the workplace and is working across industries to stamp it out and build an environment where people feel safe and able to challenge inappropriate behaviour."
At the weekend, Mr. Sullivan said he "categorically denies" all of the claims. His lawyers said he would make no further public comment when contacted after Monday's reports were published.
The Metropolitan Police said it was investigating a report relating to the "alleged taking of indecent images and sexual exploitation at locations in London and Essex in the 1980s."
The force said this investigation related to one alleged victim and was being led by specialist detectives from the Met's rape and serious sexual offences team.
Scotland Yard said: "We take all allegations of offences against women and girls extremely seriously, no matter the length of time that has passed.
"As with all cases, any information or evidence provided to police will be assessed and the appropriate inquiries carried out.
"In recent years, we have been working closely with partners across the criminal justice system to ensure that victim-survivors are at the heart of our response, with a greater focus on suspects and their offending.
"We would encourage any victims of sexual offences to come forward and speak to us on 101, or 999 in an emergency."
In a statement announcing he was stepping down as chairman of West Ham at the weekend, Mr. Sullivan said: "The false allegations levelled against me have been sensationalised by the media.
"After a lifetime spent building businesses in the adult industry, in which I have met thousands of women, it is sadly inevitable that a small number of improper conduct claims are being made against me.
"I categorically deny these claims."
He added: "After very careful consideration and with a heavy heart, I have decided to resign as joint-chair and director of West Ham United FC with immediate effect.
"This has been an incredibly painful decision to make, but it is one made out of love, respect and responsibility toward a football club and a fanbase that deserve absolute unity and focus moving forward."
Mr. Sullivan made his millions from the pornography industry throughout the 1970s.
In 1982, he was convicted of living off immoral earnings and served 71 days in prison before successfully appealing.
Mr. Sullivan and business partner David Gold completed their takeover of West Ham in 2010 after selling Birmingham City, and brought Karren Brady with them as vice-chairman.
Their tenure oversaw the move from Upton Park to the former Olympic Stadium in 2016.
Mr. Gold died in 2023, aged 86, while Baroness Brady left her role before the end of a 2025-26 season that ended in relegation from the Premier League.
Mr. Sullivan's net worth was estimated to be around £1.2 billion in 2024, according to The Times Rich List.
The Football Association has been contacted for comment. West Ham and Birmingham declined to comment.