WICHITA, Kan. (AP) — The family of an unarmed black man who was shot in the back following a police chase in Kansas has sued alleging he was beaten by officers while he lay dying from a gunshot wound.

The lawsuit filed Thursday in U.S. District Court in Kansas by the family of 24-year-old Matthew Holmes stems from an Aug. 28, 2017, incident that included a 20-mile chase of the suspect vehicle that reached speeds in excess of 100 miles per hour.

Authorities who investigated the shooting found Holmes was shot in the back by a McPherson County sheriff’s deputy while Holmes was on the ground struggling with Newton police officer.

Prosecutors declined to bring criminal charges, finding that the deputy had a reasonable belief the officer faced imminent death or great bodily harm.