US billionaire and registered sex offender, Jeffrey Epstein, was found injured and barely conscious in a Manhattan jail cell on Tuesday after a possible suicide attempt.

According to an NBC News report, the 66-year-old had marks around his neck and was in a fetal position when he was discovered by guards at the Metropolitan Correctional Center, where he is being held without bail as he awaits trial on charges connected to allegations from the early 2000s.

Law enforcement sources told NBC that Epstein was taken to a nearby hospital for treatment.

It's not clear how he got injured, but the sources said that prison investigators believed it was likely a suicide attempt.

The insiders also revealed that Investigators were also exploring other possibilities including that Epstein was attacked by one of his cellmates or that the wounds were self-inflicted in a bid to be transferred to a medical ward.

Epstein, a wealthy financier who was once friendly with Prince Andrew, former US President Bill Clinton and President Donald Trump has been accused of exploiting dozens of girls, some of them underage, for sex in New York and his Florida homes.

His is facing 45 years in prison if convicted.