(Bloomberg) -- The federal judge who was overseeing the criminal sex-trafficking case against Jeffrey Epstein asked the former warden of a New York jail whether an investigation of the financier’s hanging death will also include details about an incident last month, when he was found unconscious in his cell with marks on his neck.

Lamine N’Diaye, who was in charge of the Metropolitan Correctional Center at the time of Epstein’s death, told the judge Monday that investigations by the Federal Bureau of Investigation and the Department of Justice’s Inspector General will include the July 23 incident.

The exchange between the judge and warden was documented in three letters, the first of which was sent by the warden on Saturday, saying that Epstein had died that day in his cell, apparently of suicide. In that letter, addressed to U.S. District Judge Richard Berman and to the chief judge of the district, N’Diaye said that Epstein was found unresponsive in his cell around 6:30 a.m. and was pronounced dead at a nearby hospital around 7:37 a.m.

Once an official cause of death is determined, the judges will be notified, N’Diaye said. The letters were posted Wednesday to the online docket of the criminal case against Epstein. Attorney General William Barr on Tuesday reassigned N’Diaye to the Bureau of Prisons’ regional office, pending a review. The two guards responsible for monitoring Epstein were placed on administrative leave.

Barr vowed a thorough investigation of irregularities at the jail in lower Manhattan. The facility is under the federal Bureau of Prisons, a unit of the Justice Department.

The FBI and the Justice Department’s inspector general opened separate probes after Epstein was found dead. The Bureau of Prisons also sent a team of investigators to the jail on Wednesday.

Authorities are reviewing apparent irregularities related to Epstein’s death, including whether two guards responsible for him slept through checks of the prisoner they were supposed to conduct every 30 minutes and then falsified records to cover up the lapse, according to a person familiar with the probe.

One of the guards wasn’t an active corrections officer at the time of Epstein’s death but had been one for seven years and volunteered to work a shift overseeing him, according to a person familiar with the matter. The other guard was the only employee at the jail that morning who was working a mandatory overtime shift, the person said.

Also, Epstein’s previous cellmate had been removed and not replaced in apparent violation of rules, the person added.

Investigators are examining the staffing conditions at the facility. The Bureau of Prisons had been hobbled by a hiring freeze under President Donald Trump’s administration, although Barr lifted the freeze in April.

The jail had 18 employees working when Epstein died, including 10 on an overtime shift, according to information the Bureau of Prisons provided to the Justice Department. During the prior shift on Aug. 9, 20 employees were working, with six working overtime.

The case is U.S. v. Epstein, 19-cr-00490, U.S. District Court, Southern District of New York (Manhattan).

(Updates with status of investigations.)

To contact the reporters on this story: Bob Van Voris in federal court in Manhattan at rvanvoris@bloomberg.net;Chris Strohm in Washington at cstrohm1@bloomberg.net

To contact the editor responsible for this story: Steve Stroth at sstroth@bloomberg.net

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