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.

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 FBI, the Justice Department’s Inspector General and the New York City Medical Examiner all launched inquiries into how the high-profile inmate could have died in federal custody.

Questions have been raised as to how US financier Jeffrey Epstein was able to apparently commit suicide in his prison cell while awaiting trial on sex trafficking charges.

New York Mayor Bill de Blasio has called for a full investigation, calling it “way too convenient”.

Jeffrey Epstein’s death raises significant questions about US prison officials’ ability to protect the lives of the suspects in their custody.