By Alanne Orjoux, CNN

(CNN) -- The man authorities believe is the Golden State Killer will face yet another murder charge, authorities said Monday.

Joseph DeAngelo, 72, will be charged with the 1975 murder of Claude Snelling, with a special allegation of the use of a firearm, according to Stuart Anderson, spokesman for the Tulare County, California, District Attorney's Office.

DeAngelo has already been charged in 12 killings, including the 1978 deaths of Katie and Brian Maggiore. Police say he committed a series of killings, rapes and other crimes attributed to the so-called Golden State Killer, also known as the East Area Rapist and the Original Night Stalker.

Snelling was shot and killed in September 1975 as he charged at a masked man who was trying to abduct his daughter from his home, according to the Visalia Times Delta.

Tulare County District Attorney Tim Ward said Snelling "died trying to save his daughter from an intruder in the early morning hours. He saved his daughter, became a hero to her that night and the community."

Ward said the community was terrorized during the 18-month crime spree linked to a man dubbed the Visalia Ransacker, which culminated in Snelling's killing. The prosecutor said investigators linked the East Area Rapist and the Visalia Ransacker.

"Science and DNA played less of a role than good old-fashioned, dedicated police work," said Ward.

Authorities said DeAngelo was working as a police officer in the city of Exeter from May 1973 to August 1976, the period in which the Ransacker cases were occurring in Visalia and at the time of the Snelling homicide. The Visalia slayings ended a few months before the East Area Rapist crimes began. By then, officials said, DeAngelo had moved to the Sacramento area as an Auburn police officer.

Authorities said the Maggiores were killed after possibly spotting the Golden State Killer as they walked their dog near a home in Rancho Cordova, outside Sacramento. The complaint alleges that DeAngelo shot the couple using an "unknown caliber firearm."

DeAngelo appeared in court in late April in a wheelchair, but didn't enter a plea to the charges of murdering the Maggiores.

Decades after the killings terrified communities throughout California, authorities tracked down DeAngelo using data from an ancestry website where people submit their DNA results in hopes of tracking down relatives and ancestors.

DNA from a crime scene was matched to genetic material from a relative who was registered on genealogy sites, and authorities later obtained a discarded sample of DeAngelo's DNA.

DeAngelo, a former police officer, Vietnam veteran and mechanic, was a reclusive neighbor in Citrus Heights, a town about 16 miles northeast of Sacramento, according to residents.