In a statement Mr Barr said: "Mr Epstein's death raises serious questions that must be answered."
According to Nine News, Epstein was found unresponsive in his jail cell Saturday morning.
66-year-old Jeffrey Epstein was accused of sexually abusing dozens of underage girls and had pleaded not guilty to federal charges of sex trafficking and conspiracy. Mr Epsetin was facing up to 45 years in prison if found guilty.
Epstein reportedly was found on his cell floor covered in bruises on his neck two weeks ago, it was unclear at the time if the injuries were self-inflicted or from an assault.
This is a developing story.
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