Who is David Sullivan - football boss, 'king of porn' and alleged sexual predator?

His business partner decided to leave the industry but Sullivan was undeterred. In the years that followed, his porn empire grew rapidly as he pushed the boundaries of what was then considered acceptable content.

By the late 1970s, he was selling more than a million copies of increasingly explicit porn magazines a month, and using the publications to advertise the sex toys and pornographic films he also sold.

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He opened a chain of sex shops across the country and branched out into producing his own adult films. Several starred his girlfriend, Mary Millington, a glamour model-turned-pornographic actress who was married to another man and who took her own life at the age of 33.

Sullivan later claimed he "created the image of Mary Millington - I was like the Simon Cowell of the sex industry".

By the start of the 1980s, the News of the World reported that Sullivan was worth an estimated £10m, with more than 100 sex shops, several race horses and a plush home in Chigwell.

Allegations about his abuse of power were reported by the Sunday newspaper as early as 1981. The paper had received a complaint from a woman who said she was rejected from a job working for Sullivan after she refused to sleep with him.

One of the paper's reporters, Tina Dalgleish, responded to an advert for "promotional entertainment work". She reported that Sullivan told her she would have to have sex as part of the job and that he needed to "judge her performance". He asked her to come upstairs and strip to her underwear, she wrote, adding that she had done so, but had then got dressed and left.

In 1982 he was convicted of profiting from massage parlours in London where men were paying for sex. He spent 71 days behind bars after his nine-month sentence was reduced on appeal.

After his stint in prison, Sullivan's attention turned to more mainstream publishing.

In 1986 he launched the Sunday Sport, a mixture of bizarre, lurid and salacious stories with a steady diet of topless glamour models on many pages. It was a rapid success and a few years later the Daily Sport followed.

The newspapers ran a feature called "Countdown to 16" where readers were teased with photos of partially clothed schoolgirls. Then, with much fanfare, the girls' 16th birthdays were announced with the publication of topless photos.

At the time, 16 was the minimum age someone could legally appear topless. It was raised to 18 in 2004.

Tony Livesey, a former editor-in-chief of the Sport newspapers who is now a presenter on BBC Radio 5 Live, claimed in his book about the papers that he and Sullivan had invented the feature. He now denies this, telling the BBC it was "categorically" not his idea and that large parts of his book were fictionalised to make it appear that he "was at the centre of all stories".

In the early 1990s, Sullivan moved into Birch Hall, a sweeping home set in 12 acres of land near Theydon Bois which he spent £7.5m building. It has its own bowling alley and two swimming pools.

A few years later, in his late 40s, he fathered two children, David Junior and Jack, with his thengirlfriend Emma Benton-Hughes, a porn film actress and director.

By then he had moved into football ownership, buying Birmingham City in 1993 with David and Ralph Gold, who owned the Ann Summers chain of sex toys and lingerie shops.

Baroness Karren Brady, then aged 23, who had been working in marketing on the Sport newspapers, was installed as managing director. She is now a member of the House of Lords and a television personality, appearing as an aide to Lord Sugar on BBC One's The Apprentice.

Brady has long worked closely with Sullivan, most recently as vice-chair of West Ham, which the businessman took over with the Gold brothers in 2010.

They have faced protests from West Ham fans over the perceived lack of spending and poor on-pitch performances.

In April, Brady left the club, standing down as vice-chair with five matches of the Premier League season remaining and West Ham locked in a relegation battle. They were eventually relegated.

Sullivan has also been linked to a man named by a judge as the head of an organised crime network implicated in extreme violence and fraud.

In 2014, it was reported that he had loaned David Hunt £1m, after a failed libel action against the Sunday Times left the crime boss with an £800,000 legal bill.

At the time, Sullivan's spokesman said the deal was a "normal commercial loan secured at a normal commercial rate".

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