The Jacksonville Sheriff's Office arrest for a man they said stabbed his relative early Saturday morning.

It happened around 7:20 a.m. in the 5700-block of West 35th Street near Moncrief Road, according to detectives.

Police said 55-year-old Reginald Adams was punched and stabbed by his grandson, 26-year-old Alfred Johnson, in some type of argument.

Witnesses told police Johnson then drove off in Adams' car.

Johnson was arrested about 8 p.m. Saturday.

Police said Adams was taken to Shands Medical Center with life-threatening injuries.