New details have emerged regarding the investigation that led to an arrest in the decades-old East Area Rapist case.

Investigators in Sacramento, California, say the case hinged on information available through websites used to trace genealogical heritages.

According to the Sacramento Bee, detectives began submitting DNA found at a crime scene several years ago to multiple online services in an effort to determine more about the suspect’s family.

Sacramento County Chief Deputy District Attorney Steve Grippi said analysts then began examining the genealogies that resulted from those searches to see whether a suspect emerged.

About a week ago, investigators zeroed in on Joseph James DeAngelo, who they say was the right age and lived in areas near the crime scenes.

After that determination, Sacramento County Sheriff Scott Jones explained that investigators recovered an item discarded by DeAngelo in hopes of obtaining a DNA sample. When those results came back earlier this week, an arrest warrant was issued for DeAngelo and the suspect was arrested a short time later.

As CrimeOnline previously reported, the suspect, also identified as the Golden State Killer, was arrested Tuesday at his home in Citrus Heights.

The former police officer worked for two different departments in the years after his spree of rape and eventually murder began in the late 1970s.

He was booked into jail early Wednesday morning and is awaiting arraignment, set for Friday in Sacramento Superior Court.

DeAngelo is expected to be charged with a dozen counts of homicide across several California counties. His string of violent crime allegedly stretched 12 years beginning in 1974.

[Featured image: Joseph DeAngelo/Sacramento County Sheriff]