India, Aug. 24 -- Former Sangamon County sheriff's deputy Sean Grayson was serving a 20-year prison sentence for the fatal shooting of Sonya Massey. Grayson had been battling stage 4 colon cancer and had recently been denied early medical release by the Illinois Prisoner Review Board. His attorney confirmed on Sunday that Grayson died in custody.

The attorney did not immediately disclose the cause or circumstances of Grayson's death. His passing comes weeks after the review board unanimously rejected his request for compassionate release, ruling that he would remain behind bars despite his terminal illness.

In a joint statement after news of his death, civil rights attorneys Ben Crump and Antonio Romanucci, who represent the Massey fami...