Jeffrey Epstein, a U.S. multimillionaire financier who was last month indicted on federal sex trafficking charges, has died of suicide in his New York City jail cell.

The 66-year-old hanged himself and his body was found in the morning, sources told NBC New York. The Metropolitan Correctional Center in Manhattan said in a statement that Epstein was found unresponsive in his cell in the Special Housing Unit “from an apparent suicide” around 6:30 a.m.

“Life-saving measures were initiated immediately by responding staff,” the statement said. “Staff requested emergency medical services and life-saving efforts continued.”

Epstein arrived at a hospital n cardiac arrest and was pronounced dead there, MCC said, adding that the FBI is investigating the incident.

A senior law enforcement official told NBC News that the FBI inquiry was started out of an “abundance of caution” and that there is nothing at this point to suggest foul play.

Epstein, who was known for socializing with politicians and members of royalty, was arrested and put behind bars in July ahead of a trial. He had pleaded not guilty to charges of sex trafficking of dozens of underage girls, some as young as 14, from at least 2002 to 2005.

Esptein’s death comes soon after hundreds of pages of court documents were unsealed in New York federal court. They provided new information regarding the sex trafficking claims, including details about how his associates recruited young women and girls, including from a Florida high school, multiple reports said.

Last month, he was placed on a suicide watch after he was found in the fetal position in his jail cell with marks on his neck. Epstein told authorities at the time that he was beaten up and called a child predator, CNN reported.

Epstein has been accused for years of paying young girls for sexual acts in Florida and avoided federal criminal charges in 2008 after prosecutors brokered a deal that allowed him to plea to state charges of solicitation of prostitution from a minor and serve 13 months in jail, the New York Times said, adding that while in custody, he was allowed to leave the facility or 12 hours a day, six days a week, to work at his office.