Jeffrey Epstein was back in jail Thursday after he was found injured in the Manhattan jail where he’s being held on federal sex trafficking charges, according to people familiar with the matter.

Epstein was found in his cell Tuesday unresponsive and with bruising and marks on his neck, according to one of the people, who asked not to be named because details of the incident aren’t public. The money manager has since been treated and returned to the Metropolitan Correctional Center in lower Manhattan, where he’s been held since his arrest on July 6.

Epstein had been housed in the 10-South high-security wing but has been moved elsewhere in the facility. Investigators are probing whether Epstein was assaulted or if the injuries were self-inflicted, one person said.

The New York Post, citing unidentified people in law enforcement, reported that guards found Epstein on Tuesday evening with injuries to his neck. The newspaper didn’t specify how Epstein had suffered the injuries. NBC News reported that investigators have questioned another inmate, Nicholas Tartaglione, a former police officer accused of a quadruple homicide.

Calls to Epstein’s lawyer Martin Weinberg and representatives of the Federal Bureau of Prisons weren’t immediately returned. A spokesperson for the U.S. Attorney’s Office in Manhattan declined to comment.

Epstein is accused of molesting teenage girls from 2002 to 2005. He has pleaded not guilty to charges of sex trafficking in minors and conspiracy and says he has fully complied with the law for more than 14 years. He pleaded guilty in 2008 to Florida state charges of soliciting prostitution and served 13 months in prison, after U.S. prosecutors in that state agreed not to charge him with federal offenses.

--With assistance from Christopher Kingdon, Bob Van Voris, Chris Dolmetsch and Gerald Porter Jr.