Shortly before 8 a.m. on Tuesday morning, police and fire crews were called to the facility, where 55-year-old David Gerhard, of Hedgesville, West Virginia, was found unresponsive in the medical unit, officials say.
Members of the Arlington County police department and sheriff's office attempted to revive Gerhard, but he died after being rushed to the Virginia Hospital Center.
Gerhard has been held in the Arlington County Detention Facility since November for failing to comply with support obligations and contempt of court.
An autopsy will now be conducted by the Office of the Chief Medical Examiner to determine the exact cause of death.
The investigation is ongoing.
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