Prosecutors accused Mr. Epstein of orchestrating a yearslong sex-trafficking operation involving girls as young as 14.

Disgraced former financier Jeffrey Epstein died Saturday morning in an apparent suicide in his Manhattan jail cell as he was awaiting trial on sex-trafficking charges, law-enforcement officials say. Mr. Epstein, 66 years old, was found unresponsive in his cell at approximately 6:30 a.m. on Saturday, according to prison officials. He was then transported to a local hospital, where he was pronounced dead. The Federal Bureau of Investigation and the Justice Department’s inspector general have opened separate investigations into the circumstances of Mr. Epstein’s death, officials said. Attorney General William Barr said in a statement he was appalled to learn of the apparent suicide. “Mr. Epstein’s death raises serious questions that must be answered,” Mr. Barr said. Mr. Barr was livid to learn about Mr. Epstein’s death, telling staffers he is determined to get to the bottom of what happened, a person familiar with the matter said.

Sen. Ben Sasse (R., Neb.), chairman of the Senate Judiciary Oversight Committee who originally asked the Justice Department to investigate the handling of the Epstein case, said in a letter to Mr. Barr: “Every single person in the Justice Department—from your Main Justice headquarters staff all the way to the night-shift jailer—knew that this man was a suicide risk, and that his dark secrets couldn’t be allowed to die with him.” He added, “Obviously, heads must roll.”

In the early 2000s, Mr. Epstein was known for his reported ties to public figures such as former President Clinton and Prince Andrew, both of whom flew on Mr. Epstein’s private jets. At the same time, the financier was dogged by allegations of sexual misconduct involving underage girls.

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