The disgraced financier should have been checked on by guards in his cell every 30 minutes, but that did not happen on the night before his apparent suicide, a law enforcement official was quoted by the paper as saying.
Epstein, 66, had been denied bail and faced up to 45 years behind bars on federal sex trafficking and conspiracy charges. He had pleaded not guilty and was awaiting trial.
Epstein had been placed on suicide watch after he was found just over two weeks ago with bruising on his neck, but according to reports was taken off the watch at the end of July.
Attorney-general William Barr said he was “appalled” to learn of Epstein’s death while in federal custody.
“Mr Epstein’s death raises serious questions that must be answered,” Barr said in a statement.
Nebraska Senator Ben Sasse said in a scathing letter to Barr that “heads must roll” after the incident.
“Every single person in the Justice Department – from your Main Justice headquarters staff all the way to the nightshift jailer – knew that this man was a suicide risk, and that his dark secrets couldn’t be allowed to die with him,” Mr Sasse wrote.
Epstein’s removal from suicide watch would have been approved by both the warden of the jail and the facility’s chief psychologist, said Jack Donson, a former prison official who worked for the Bureau of Prisons for more than two decades. On Friday, more than 2,000 pages of documents were released about a since-settled lawsuit against Epstein’s former girlfriend by Virginia Giuffre, one of his accusers.
The records contain graphic allegations against Epstein, as well as the transcript of a 2016 deposition of Epstein in which he repeatedly refused to answer questions to avoid incriminating himself.
Epstein’s arrest drew national attention focusing on a deal that allowed him to plead guilty in 2008 to soliciting a minor for prostitution in Florida and avoid more serious federal charges.
Before his legal troubles, Epstein led a life of extraordinary luxury, socialised with princes and presidents and lived on a 100-acre private island.