The assailant stalked victims and waited for them to be alone, Hestrin said.
“And then he would take his chance and opportunity to hold them at gunpoint or knifepoint and violently rape them and assault them,” he said.
Cooke pleaded not guilty to all counts during his arraignment and was scheduled to appear in court on July 31 for a preliminary hearing, district attorney spokesman John Hall said.
There were no immediate details available about investigations at the times of the crimes.
An arrest warrant based on the DNA profile of a “John Doe” was obtained by Riverside police in 2015, leading to a criminal complaint against that unknown person.
Last year, a Corona police detective and a forensic technician began looking into sexual assault cold cases, compared notes with Riverside detectives and found a DNA match between a case in each city, Corona Police Chief George Johnstone said.
In January, a DNA sample was submitted to the FBI’s genetic genealogy team, and the technology identified a potential pool of suspects.
Cooke was identified as a person of interest, and it was learned he lived in Riverside and Corona during the times of the rapes, Johnstone said.
Investigators collected trash bags from Cooke’s Chino Valley, Arizona, home and matched DNA to the California crimes, the district attorney’s office said.
Cooke was arrested on May 26 in Prescott, Arizona, and extradited to California on June 14.
The criminal complaint charges him with six counts of forcible rape, four counts of forcible oral copulation, three counts of assault with intent to commit rape or oral copulation during a first-degree burglary, two counts of kidnap with intent to commit rape or oral copulation, and one count of forcible sexual penetration.
Eleven counts involve crimes in Riverside in 1996 and 1998. Five counts involve crimes in Corona in 2007.
Cooke faces a potential life sentence if convicted.