NEW YORK (Reuters) - Disgraced financier Jeffrey Epstein was found dead on Saturday after an apparent suicide in the New York jail cell where he was being held without bail on sex-trafficking charges, and a source said he was not on suicide watch at the time of his death.

Epstein, 66, was found unresponsive in his cell in the Special Housing Unit of the Metropolitan Correctional Center (MCC) and taken to a hospital where he was pronounced dead, the Federal Bureau of Prisons, which operates the lower Manhattan jail, said in a statement. It declined to comment further.

Epstein, a well-connected money manager dogged for years by allegations that he sexually abused girls and young women, was found hanging by his neck, according to the source, who was not authorized to speak on the record.

The financier, who once counted Republican President Donald Trump and Democratic former President Bill Clinton as friends, was arrested on July 6 and pleaded not guilty to charges of sex trafficking involving dozens of underage girls as young as 14, from at least 2002 to 2005.

The FBI and the Department of Justice’s Inspector General were opening investigations into his death, U.S. Attorney General William Barr said, adding that he was “appalled” to learn of the apparent suicide in federal custody.

Last month, Epstein was found unconscious on the floor of his jail cell with marks on his neck, and officials were investigating that incident as a possible suicide or assault.

“Mr. Epstein’s death raises serious questions that must be answered,” Barr said in a statement.

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Even though Epstein was found unconscious last month, he had recently been taken off suicide watch, a special set of procedures for inmates in danger of taking their own life, according to the source. The financier was in a cell by himself when his body was found.

It was not immediately clear why Epstein was taken off suicide watch.

At the MCC, two jail guards are required to make separate checks on all prisoners every 30 minutes, but that procedure was not followed overnight, according to the source. In addition, every 15 minutes guards are required to make another check on prisoners who are on suicide watch.

Guards generally remove any prisoner placed on suicide watch from the Special Housing Unit where Epstein was housed, according to a Twitter post by Preet Bharara, a former Manhattan-based U.S. attorney. The unit separates inmates such as accused sex offenders from the general population for their protection.

Aja Davis, a spokeswoman for the New York City Office of the Chief Medical Examiner, said she could not say how Epstein died before her office examined the body.

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INVESTIGATION TO CONTINUE

Epstein was arrested on July 6 at a New Jersey airport after taking a private plane from Paris. Last month, a judge refused Epstein’s request to release him on bail and allow him to live under 24-hour guard in his opulent townhouse on Manhattan’s Upper East Side. The financier was appealing that ruling.

The indictment accused Epstein of knowingly recruiting underage women to engage in sex acts with him, sometimes over a period of years while paying the women for each encounter.

Prosecutors said a search of his townhouse, conducted under a warrant, uncovered evidence of hundreds, and perhaps thousands, of nude photographs of “what appeared to be underage girls,” including some photos cataloged on compact discs and kept in a locked safe.

In a court filing on July 25, the government said it was pursuing an “ongoing investigation of uncharged individuals” in connection with the case.

That investigation, by the U.S. Attorney’s Office in Manhattan, will continue despite Epstein’s death, a different source familiar with the matter said.

“Today’s events are disturbing, and we are deeply aware of their potential to present yet another hurdle to giving Epstein’s many victims their day in court,” Geoffrey Berman, the U.S. Attorney in Manhattan, said in a statement. “Our investigation of the conduct charged in the indictment – which included a conspiracy count – remains ongoing.”

In addition to Trump and Clinton, Epstein has socialized with L Brands founder Les Wexner over the years, and according to court papers, with Britain’s Prince Andrew. None of them was mentioned in the indictment against Epstein.

The charges were announced more than a decade after he pleaded guilty in Florida to state charges of solicitation of prostitution from a minor in a deal with prosecutors that has been widely criticized as too lenient.

One of the Florida prosecutors, Alexander Acosta, resigned as U.S. labor secretary in July as the deal came under fresh scrutiny after Epstein’s arrest in New York.

His death came a day after the unsealing of a court filing in which a woman who accused Epstein of keeping her as a sex slave said one of the financier’s associates had instructed her to have sex with at least a half-dozen prominent men.

The claim by Virginia Giuffre came in a deposition that was included in about 2,000 pages of documents related to her defamation lawsuit against Ghislaine Maxwell, the associate whom Giuffre said helped Epstein procure girls for sex.

Lawyers for Maxwell did not respond to several phone and email requests for comment.