This comes just two weeks after the former multi-millionaire investment banker was placed on suicide watch as he awaited trial on a slew of charges, including child sex trafficking.
The development has major implications for the investigation, which raised questions about some of the world’s most influential political and entertainment leaders, and their potential knowledge and/or role in the alleged crimes.
The prison in Lower Manhattan where 66-year-old Epstein was found dead is known around the world as MCC, short for Manhattan Correctional Center.
It is a U.S. federal detention facility operated by the Federal Bureau of Prisons. The notorious lockup is regarded for having some of the tightest security measures in the world. MCC has housed some of the world’s most infamous criminals, including mob boss John Gotti, Mexican drug lord El Chapo, World Trade Center bombers Ramzi Youself and Omar Abdel-Rahman known as the “the Blind Sheikh,” as well as Ponzi scheme mastermind Bernie Madoff.
R&B singer R. Kelly also spent time in the same solitary unit at MCC where Epstein was while facing charges in multiple states on child porn and sex abuse charges.
On Friday Kelly's lawyer told the singer's hometown newspaper The Chicago Sun-Times that Kelly was "miserable."
“Now he’s been placed in the MCC’s ‘SHU’ — a cell in solitary confinement away from the jail population and is constantly being moved from cell to cell. He has only the guards to talk to.”
The Federal Bureau of Prisons said in a statement Saturday that Epstein was found unresponsive in his cell in the Special Housing Unit.
"Mr. Epstein was transported by EMS to a local hospital for treatment of life-threatening injuries, and subsequently pronounced dead by hospital staff. The FBI is investigating the incident."
U.S. Attorney General William P. Barr released a statement, saying he is appalled.
"Mr. Epstein's death raises serious questions that must be answered. In addition to the FBI's investigation, I have consulted with the Inspector General who is opening an investigation into the circumstances of Mr. Epstein's death."
The U.S. Attorney's office for the Southern District of New York is calling the chain of events "disturbing".
A defendant in the 1998 American embassy bombings in Africa spent time at both MCC and Guantanamo Bay, and once bemoaned that the New York City lockup was worse.
MCC was the site of a sensational escape attempt in 1981 when an armed Bonnie-and-Clyde-type duo reportedly highjacked a sightseeing helicopter and landed on the lockup’s roof in an unsuccessful attempt to spring a drug dealer free.
This story has been updated.