"Mr. Epstein’s death raises serious questions that must be answered," he said, adding that he had consulted with the Department of Justice's Inspector General, who is opening an investigation into the circumstances around the death.
The FBI also is investigating, Barr said.
Epstein, 66, was found unresponsive in his cell in the Special Housing Unit of the Metropolitan Correctional Center and transported to a local hospital where he was pronounced dead, the Federal Bureau of Prisons, which operates the lower Manhattan jail, confirmed on Saturday.