The New York City medical examiner ruled Jeffrey Epstein's death a suicide on Friday, confirming after nearly a week of speculation that the financier hanged himself in his jail cell.

Epstein, 66, was found dead in his cell at the Metropolitan Correctional Center in New York City on Aug. 10, touching off outrage and disbelief over how such a high-profile prisoner could have gone unwatched.

Chief Medical Examiner Dr. Barbara Sampson said in a statement that she made the suicide determination "after careful review of all investigative information, including complete autopsy findings."

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

One of Epstein's lawyers, Marc Fernich, declined to comment. An office telephone number for Dr. Michael Baden, the pathologist hired by Epstein's representatives to observe the autopsy, rang unanswered.

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 investigating Epstein's death.

Watch: U.S. attorney general appalled by 'irregularities' at Epstein's jail

U.S. Attorney General William Barr says the Manhattan jail where Jeffrey Epstein was being held "failed to adequately secure this prisoner." 3:20

After Epstein's death, U.S. Attorney Geoffrey Berman said the federal investigation into the allegations against him remains steadfast.

Barr also warned that "any co-conspirators should not rest easy."

"Let me assure you that this case will continue on against anyone who was complicit," Barr said. "The victims deserve justice, and they will get it."

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.

Both were working overtime because of staffing shortages, the people said. They spoke on condition of anonymity because they lacked authorization to publicly discuss the investigation.

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.

Autopsy reports are not public records in New York, and the details of the medical examiner's finding, or the evidence she relied upon, were not immediately available.

Lawsuits against estate

Epstein was a wealth manager who hobnobbed with the rich, famous and influential, including presidents and a prince.

He owned a private island in the Caribbean, homes in Paris and New York City, a New Mexico ranch and a fleet of expensive cars. His friends had once included Britain's Prince Andrew and Bill Clinton and Donald Trump. Clinton and Trump both said they had not seen Epstein in years when new charges were brought against him last month.

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

The suit, filed 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 US 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.