As attorney general William Barr condemned “serious irregularities” at the jail where he was being held on bail, and the world waited news of details of an autopsy amid huge speculation and frenzied conspiracy theories, it emerged the 66-year-old disgraced financier had not been checked for several hours before he was found dead in his cell.

Epstein, who was last month arrested and accused of orchestrating a sex trafficking network involving girls as young as 14, had not been on suicide watch at the time of his death.

Regulations did call for him to be checked every 30 minutes, however. These rules were put into place after the man who was once a friend of multiple powerful men and celebrities, was was last month found unconscious on the floor of his cell with marks on his neck, an episode officials were investigating as possible suicide attempt or assault.

The New York Times said only one of the two people who were monitoring Epstein at the Metropolitan Correctional Centre in New York City, was a “fully-fledged correctional officer”.

Jeffrey Epstein: Controversies surrounding paedophile billionaire Show all 9 1 /9 Jeffrey Epstein: Controversies surrounding paedophile billionaire Jeffrey Epstein: Controversies surrounding paedophile billionaire Jeffrey Epstein in court Billionaire financier Jeffrey Epstein attends court as he pleads guilty to solicitation and procuring a person under the age of 18 for prostitution, 2008 Zuma/Rex Jeffrey Epstein: Controversies surrounding paedophile billionaire Jeffrey Epstein in court Billionaire financier Jeffrey Epstein pleaded guilty in 2008 to felony solicitation and procuring a person under the age of 18 for prostitution. He was sentenced to 18 months in jail. Epstein, allegedly paid several girls under the age of 18 in return for naked massages at his Palm Beach, Florida estate Zuma/Rex Jeffrey Epstein: Controversies surrounding paedophile billionaire Jeffrey Epstein's car Jeffrey Epstein is whisked away from the Palm Beach County jail in a black car shortly after 6am on 22 July 2009. Epstein left the jail through the sally port, where prisoners are brought in, rather than through the main doors where prisoners are routinely released Zuma/Rex Jeffrey Epstein: Controversies surrounding paedophile billionaire Jeffrey Epstein's mugshot Billionaire Jeffrey Epstein's mugshot, taken after he was indicted for soliciting a prostitute on 26 July 2006. Beginning in mid-March 2005, Epstein became the target of a sexual battery probe conducted by the Palm Beach Police Department, according to the affidavit, which alleges that Epstein paid a series of underage girls to engage in sexual activity with him. In a 2002 New York magazine profile of Epstein, Donald Trump called the moneyman a 'terrific guy' who 'likes beautiful women as much as I do, and many of them are on the younger side.' Epstein, who reportedly runs a multibillion-dollar investment fund, travels in his own Boeing 727 (upon which he has transported Bill Clinton to Africa) and owns a 45,000-square-foot mansion on Manhattan's Upper East Side Palm Beach County Sheriff's Department Jeffrey Epstein: Controversies surrounding paedophile billionaire Jack Goldberger, Jeffrey Epstein's attorney Jeffrey Epstein's attorney, Jack Goldberger, talks with reporters gathered outside the Palm Beach County jail on 22 July 2009 after Epstein was whisked away from the jail in a black car Zuma/Rex Jeffrey Epstein: Controversies surrounding paedophile billionaire Jeffrey Epstein Florida Police department sexual offenders database picture of Jeffrey Epstein taken in 2013 Jeffrey Epstein: Controversies surrounding paedophile billionaire Jeffrey Epstein's mansion His Palm Beach mansion in Florida Google Jeffrey Epstein: Controversies surrounding paedophile billionaire Jeffrey Epstein's island The private Caribbean island, Little St James is part of the US Virgin Islands NBC News Jeffrey Epstein: Controversies surrounding paedophile billionaire Jeffrey Epstein's island The private Caribbean island, Little St James is part of the US Virgin Islands NBC News

“We are now learning of serious irregularities at this facility that are deeply concerning and demand a thorough investigation,” said Mr Barr, who ordered two separate investigations into what happened.

“We will get to the bottom of what happened. There will be accountability.”

Speaking at a national policing conference in New Orleans on Monday morning, Mr Barr insisted that despite Epstein being found dead a day after new details were unsealed of the allegations against him, investigators would continue to probe the backdrop of those claims. Many of the numerous women to have accused Epstein of abuse, accusations he had most recently denied, had voiced regret they would now not get justice.

“Let me assure you that this case will continue on against anyone who was complicit with Epstein,” said Mr Barr. “ Any co-conspirators should not rest easy. The victims deserve justice and they will get it.”

The New York City medical examiner said an autopsy had been completed on Epstein on Sunday, but that a determination on the cause of his death was still pending.

In the hours after the financier’s death on Saturday morning, Donald Trump, who was once one of Epstein’s friends or associate and in 2002 told a journalist he was “a terrific guy”, retweeted a conspiracy theory posted by a conservative comedian suggesting – without merit – Bill Clinton and his family were behind the prison death.

Fox & Friends hosts push Epstein conspiracy theories on live TV

Epstein was arrested on July 6 and pleaded not guilty to federal charges of sex trafficking involving dozens of underage girls as young as 14, from at least 2002 to 2005.