Seven people employed by Backpage.com, including its two founders, were indicted on federal charges in what authorities say was a scheme to knowingly facilitate prostitution by running ads for sexual services which made $500million.

The 93-count indictment, which also includes money laundering charges, was unsealed Monday after Backpage.com and its affiliated websites were seized Friday by US federal law enforcement authorities and taken off the internet.

Website founders Michael Lacey and James Larkin are charged with facilitating prostitution and money laundering.

They are already facing state money laundering charges in California.

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Seven people employed by Backpage.com, including its two founders Michael Lacey (left) and James Larkin (right), were indicted on federal charges in what authorities say was a scheme to knowingly facilitate prostitution by running ads for sexual services

The 93-count indictment, which also includes money laundering charges, was unsealed Monday after Backpage.com and its affiliated websites were seized Friday by US federal law enforcement authorities and taken off the internet

Larry Kazan, who represents Lacey, didn't return a call seeking comment. There is no listing for Larkin's attorney.

The indictment alleges that Backpage.com on some occasions had helped customers edit their ads so they would stay within legal limits while still encouraging commercial sex.

'For far too long, Backpage.com existed as the dominant marketplace for illicit commercial sex, a place where sex traffickers frequently advertised children and adults alike,' Attorney General Jeff Sessions said in a statement.

'But this illegality stops right now.'

Lawmakers and law enforcement officials have for years been working to crack down on the website, which was used primarily to sell sex and was the second largest classified ad service in the United States after Craigslist.

Backpage and some advocacy groups have argued that the ads on the site were free speech protected by the US Constitution.

The unsealed indictment, returned by a federal grand jury in Arizona, lays out details concerning 17 alleged victims, including both adults and minors as young as 14 years old, who were trafficked on the site.

In one case, a customer murdered one of the victims and attempted to burn her corpse, an official from the US Attorney's Office in Arizona said.

Later, when the victim's father tried to have his daughter's pictures and ads taken down, the website did not immediately comply, according to the official.

In another 2012 lawsuit three individuals in Illinois said they were between 13 and 15 years old when they were advertised on Backpage. They reached a controversial settlement in the case last year.

Other cases against the website remain pending in Washington, California and Texas.

In addition to charging Larkin and Lacey, the indictment also charged Backpage.com's executive vice president Scott Spear, its chief financial officer John 'Jed' Brunst, its sales and marketing director Dan Hyer, operations manager Andrew Padilla and its assistant operations manager Joyce Vaught.

The court records did not yet list any attorneys for Spear, Brunst, Hyer or Padilla, and an attorney for Vaught could not immediately be reached.

The indictment alleges that Backpage.com on some occasions had helped customers edit their ads so they would stay within legal limits while still encouraging commercial sex. Backpage.com CEO Carl Ferrer, left, along with former co-owners Michael Lacey (M) and James Larkin (R), in Sacramento Superior Court on October 12, 2016

In the indictment, the US Justice Department accuses Backpage of earning $500million in prostitution-related revenue since its inception in 2004, and of money laundering that entailed routing funds through seemingly unrelated entities, wiring money in and out of foreign accounts and converting it into and out of bitcoin and other cryptocurrencies. Pictured are Larkin, Lacey and Ferrer in court in 2017

In the indictment, the US Justice Department accuses Backpage of earning $500million in prostitution-related revenue since its inception in 2004, and of money laundering that entailed routing funds through seemingly unrelated entities, wiring money in and out of foreign accounts and converting it into and out of bitcoin and other cryptocurrencies.

Prosecutors also alleged that the website's employees sought to actively mislead the public about its sincerity of efforts to prevent prostitution ads.

The website's 'escort' section was finally shut down in 2017.

The indictment said that in private, Lacey 'bragged about the company's contributions to the prostitution industry, writing in one internal document "Backpage is part of the solution."'

The indictment relies on the same law used in a similar case in California several years ago against the founder of MyRedbook.com, who pleaded guilty to charges that the website hosted ads largely posted by prostitutes.

In October 2016, the CEO of backpage.com, Carl Ferrer, was arrested in Houston on felony pimping charges after arriving back to the US from Amsterdam. Those charges were later dropped

A Justice Department official said the case against Backpage does not rely on sex trafficking charges, but rather on charges connected to prostitution, which are easier to prosecute.

To prove sex trafficking, prosecutors would need to show each individual ad either involved a minor, or featured an adult who was selling sex through force or coercion.

In October 2016, the CEO of backpage.com, Carl Ferrer, was arrested in Houston on felony pimping charges after arriving back to the US from Amsterdam.

Ferrer, 55, was charged with pimping a minor, pimping and conspiracy to commit pimping, according to NPR.

Charges were dropped against Ferrer two months later, with the court ruling that the law has 'precluded liability for online publishers for the action of publishing third party speech and thus provided for both a foreclosure from prosecution and an affirmative defense at trial.'

'Congress has spoken on this matter and it is for Congress, not this Court, to revisit,' Judge Michael Bowman said in his decision.

Efforts to get that law changed were featured prominently in a Netflix documentary called 'I am Jane Doe.' Pictured is a grab from the documentary

Last month, Congress passed legislation that makes it easier for state prosecutors and sex-trafficking victims to sue website operators that facilitate online sex trafficking.

The bill, which President Donald Trump is expected to sign into law this week, amends the Communications Decency Act, which largely shielded website operators from state criminal charges or civil liability if they were facilitating sex ads or prostitution.

Efforts to get that law changed were featured prominently in a Netflix documentary called 'I am Jane Doe.'