The 63-year-old inmate, who passed away while inside the Coconino County Jail Sunday, died of natural causes. Coconino County Sheriff’s officials say medical staff were conducting a medical assessment on Floyd Jackson at around 7:16 a.m. when he became unresponsive in his cell. Staff and officers began life-saving measures, including CPR on Jackson. Paramedics arrived and took over efforts, but he was pronounced dead at 7:46 a.m. Jackson was transported from Maricopa County to Coconino County on Thursday after he was arrested on a warrant for failure to comply for driving on a suspended license out of Flagstaff. He was in a cell by himself. The Coconino County Medical Examiner’s office says Jackson died of peptic ulcer disease, which is considered a natural cause.