A 63-year-old inmate died of unknown causes Thursday at San Diego Central Jail.
Kenneth Galen Bach of Chula Vista was found unconscious and unresponsive in his cell at the Front Street detention center about 4 a.m., according to the San Diego County Sheriff's Department.
Despite lifesaving attempts on the part of deputies and jail medical staff, Bach was pronounced dead at the scene.
Bach was arrested Monday on suspicion of felony vandalism and issuing criminal threats, sheriff's Lt. Joseph Jarjura said.
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The cause and manner of his death will be determined by the county Medical Examiner's Office.
"We extend our sympathies to the Bach family and (others) affected by his passing," Jarjura said. "A sheriff's family-liaison officer will support the family as they deal with their loss."
The county has had 12 in-custody deaths this year. The last one was on July 20.
