(CNN) Financier and accused sex trafficker Jeffrey Epstein was found in his Manhattan jail cell with marks on his neck this week, a law enforcement source and a source familiar with the incident said Thursday.

It is not clear to jail officials if the injuries, incurred Tuesday, were self-inflicted or the result of an assault, the law enforcement source said.

While Epstein told authorities he was beaten up and called a child predator, the sources said, he has been placed on suicide watch. His injuries were not serious, they said.

The Federal Bureau of Prisons, citing privacy and security concerns, declined to comment on the matter, other than to say that Epstein remains housed at Metropolitan Correctional Center, New York and is not in the hospital.

A source who stood several feet away from Epstein on Thursday said he has no cuts or bruises on his face and didn't visibly appear injured. The source said it was difficult to notice whether Epstein had any markings on his neck because the jumpsuit he wore covered part of his neck. Epstein was meeting with his attorneys, the source said.

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