Philadelphia law-enforcement officials say they’ve solved a 28-year-old cold-case murder by using new technology to tie a sock found at a crime scene to a longtime suspect in the case. Theodore Dill Donahue, 52, was arrested Tuesday on charges of murder and abuse of a corpse, among other charges, in connection with the slaying of his former girlfriend Denise Sharon Kulb. Investigators built the case against him using new tools, including photo-enhancing technology that connected Donahue to a lone yellow sock found at the crime scene, officials said. Kulb’s body was found on Nov. 15, 1991, clothed only in a sweater, and piled on top were two pairs of pants, a T-shirt, a jacket, and one yellow sock, The Philadelphia Inquirer reports. State troopers searched Donahue’s apartment on the same day, and found one yellow sock that matched the sock found on the body, and a job application with Kulb’s name on it. The photos of the socks were enhanced since the case was re-opened to make the connection between Donahue’s apartment and the crime scene. Anthony Voci, supervisor of the district attorney’s homicide unit, said Donahue’s arrest nearly three decades after he allegedly killed Kulb “demonstrates our commitment to the ideal that there is no case, no amount of time, that we consider a lost cause.”