OKLAHOMA CITY (KFOR) — An investigation is underway after a 63-year-old Oklahoma County Department of Corrections inmate reportedly died on Thursday morning. Sandra Cunningham. Photo courtesy Oklahoma County Department of Corrections. According to the OCDC, Sandra Cunningham was found unresponsive in her cell at around 7:51 a.m. while a detention officer and medical staff member were distributing medication. Staff performed lifesaving efforts and took Cunningham to the hospital. She died shortly after at 8:37 a.m. Oklahoma executes inmate convicted of shooting, killing man during 1992 robbery Cunningham had been booked into the facility on September 15—11 days before her death—on a felony charge of possession of controlled substance and misdemeanor charges of possession of controlled substance and possession of paraphernalia. She also had a hold from Tulsa County. The OCDC says Cunningham did not have a cellmate and was last seen by an officer and on video at around 6:41 a.m. At that time, there were reportedly no obvious signs leading to a potential cause of death. The cause of Cunningham's death is still being determined as the investigation is still in its preliminary stage.