Matthew Muller, who is currently serving a 40-year sentence for the kidnapping of Denise Huskins, pled guilty Friday in Santa Clara County court on new charges of medicating and then sexually assaulting another woman.

Muller was in prison for the infamous Vallejo kidnapping when he implicated himself in unsolved attacks in Palo Alto and Mountain View, prompting a renewed investigation and DNA analysis.

Matthew Muller was convicted of kidnapping and sexual assault in a 2015 case in which Vallejo police initially accused the victim and her boyfriend of making up the story of her abduction. He pleaded guilty this week in two additional cases.