An Arizona man has been accused of a murder spree in which he allegedly killed nine people in three weeks, a rampage that would make him one of the most prolific serial killers in the state’s history. Cleophus Cooksey Jr., 35, was arrested on Dec. 17, 2017, after police responded to a call of shots fired in Phoenix. When officers arrived they found Cooksey’s mother and stepfather dead. Cooksey was not linked to the other homicides until he was in custody, police said Thursday. Investigators used shell casings to link the other murders, police said. Phoenix Mayor Greg Stanton said new technology allowed officers to determine the evidence was linked to the suspect quickly. Cooksey’s other alleged victims include the brother of his ex-girlfriend and various men and women of black, white and Hispanic race and ethnicity.