During a joint news conference held in Santa Ana, prosecutors also announced the filing of 13 additional kidnapping charges against Joseph DeAngelo, 72, as part of an amended complaint in Sacramento County that consolidates all the charges against him.
DeAngelo faces murder charges for killings that occurred across the state in the 70s and 80s - including a couple in Dana Point and two women in Irvine. In addition, he is accused of other murders in Ventura, Goleta, Visalia and Rancho Cordova.
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The 72-year-old former police officer is believed to be behind more than 50 rapes in Northern California. He is currently in jail in Sacramento.
Investigators said they used a public genealogy database to tie DeAngelo's DNA to items discarded at crime scenes.
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DeAngelo remains in custody, has not entered a plea and is expected back in court on Thursday in Sacramento.
KGO-TV contributed to this report.