Mr. Epstein was housed in a special unit with extra security, but he was not under suicide watch, according to a prison official.
The authorities could not immediately explain why they had not put additional safeguards in place after the earlier incident. The F.B.I. said it was investigating, and Attorney General William P. Barr said in a statement that a special inquiry would be opened into what happened.
I was appalled to learn that Jeffrey Epstein was found dead early this morning from an apparent suicide while in federal custody, Mr. Barr said. Mr. Epsteins death raises serious questions that must be answered. In addition to the FBIs investigation, I have consulted with the Inspector General who is opening an investigation into the circumstances of Mr. Epsteins death.