Jeffrey Epstein's prison death has been ruled a suicide, the medical examiner's office said Friday.

Epstein, 66, was found dead in his cell at the Metropolitan Correctional Centre in New York City on August 10, sparking outrage and disbelief over how such a high-profile prisoner, known for socialising with powerful people including presidents Donald Trump and Bill Clinton, could have gone unwatched.

The Bureau of Prisons said Epstein had apparently killed himself, but that didn't squelch conspiracy theories about his death.

Epstein, who was charged with sexually abusing numerous underage girls over several years, had been placed on suicide watch last month after he was found on his cell floor on July 23 with bruising on his neck.

But multiple people familiar with operations at the jail say he was taken off the watch after about a week and put back in a high-security housing unit where he was less closely monitored, but still supposed to be checked on every 30 minutes.

Attorney General William Barr says officials have uncovered "serious irregularities" at the jail. The FBI and the Justice Department's inspector general are both investigating Epstein's death.

Jail guards on duty the night of Epstein's death are suspected of falsifying log entries to show they were checking on inmates every half hour as required, according to several people familiar with the matter.

A guard in Epstein's unit was working a fifth straight day of overtime and another guard was working mandatory overtime, the people said. They spoke on condition of anonymity because the lacked authorisation to publicly discuss the investigation.

US District Judge Richard Berman, who is in charge of the criminal case against Epstein, asked the jail's warden this week for answers about the earlier episode, writing in a letter Monday that it had "never been definitively explained".

The warden replied that an internal investigation was completed but he couldn't provide information because the findings were being incorporated into investigations into Epstein's death.

The Associated Press often does not report details of suicide methods, but has made an exception because Epstein's cause of death is pertinent to the ongoing investigations.

The Washington Post and The New York Times reported Thursday that the autopsy revealed that several bones in Epstein's neck had been broken, leading to speculation his death was a homicide.

Chief Medical Examiner Barbara Sampson issued a statement on Thursday in response to those articles, saying: "In all forensic investigations, all information must be synthesised to determine the cause and manner of death. Everything must be consistent; no single finding can be evaluated in a vacuum."

The medical examiner's ruling came a day after two more women sued Jeffrey Epstein's estate, saying he sexually abused them.

The suit, filed Thursday in a federal court in New York, claims the women were working as hostesses at a popular Manhattan restaurant in 2004 when they were recruited to give Epstein massages.

One was 18 at the time. The other was 20.

The lawsuit says an unidentified female recruiter offered the hostesses hundreds of dollars to provide massages to Epstein, saying he "liked young, pretty girls to massage him," and wouldn't engage in any unwanted touching. The women say Epstein groped them anyway.

One plaintiff now lives in Japan, the other in Baltimore. They seek $100 million in damages, citing depression, anxiety, anger and flashbacks.

Other lawsuits, filed over many years by other women, accused him of hiring girls as young as 14 or 15 to give him massages, then subjecting them to sex acts.

WHERE TO GET HELP:

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