Former Illinois sheriff’s deputy Sean Grayson, who was convicted of fatally shooting Sonya Massey in 2024, has died while serving a 20-year prison sentence.

Grayson, 32, had been diagnosed with advanced colon cancer that had spread to several organs, but it was not immediately confirmed whether cancer caused his death.

Grayson shot Massey three times after responding to her 911 call about a prowler, despite her apologizing and dropping to the floor after he threatened to shoot her.

The shooting, captured on body-camera footage, sparked protests and calls for justice, and Grayson was convicted of murder last year, NBC News has reported.

Following Massey’s death, Illinois enacted the Sonya Massey Act requiring stricter background checks for law enforcement hires, while Sangamon County agreed to a $10 million settlement with her family.