SAN FRANCISCO AP – For 25 years, the unsolved murder of 9-year-old Mei Leung haunted San Francisco police homicide Inspector Holly Pera, a novice patrol officer at the time who now helps solve the department’s cold cases.

On Thursday, Pera – who revived the case about five years ago – and San Francisco police said DNA evidence has linked the infamous serial killer Richard Ramirez, known as the “Night Stalker,” to the April 10, 1984 homicide.