A Bucks County man was sentenced to 60 to 120 years in prison this week for raping at least six children, which prosecutors said they believe is only a fraction of the man's criminal history.

William Charles Thomas, 59, of Falls Township, pleaded no contest to raping and indecently assaulting six girls from 1990 to the present. He also pleaded guilty to multiple child pornography charges in which a seventh victim was identified. Bucks County Judge Wallace H. Bateman Jr. sentenced him to a concurrent 40 to 100 years for those crimes.

"It's clear to me that as long as you are in the community, the children of our community are at risk," the judge told Thomas in the hearing Monday. "Your depravity is without limitation."

Thomas worked as a handyman in the trailer park where he lived. Prosecutors said most of Thomas' victims were the children of neighbors or customers, for whom he sometimes worked as a babysitter.

He was charged last year after the manager of the trailer park discovered a piece of plywood bearing handwritten details of sexual assaults on two girls, including the names of the victims. Police later found hundreds of items of additional evidence in the home.

Deputy District Attorney Jennifer M. Schorn, who prosecuted the case, told Bateman that there are other victims depicted in Thomas' writings whom police have not been able to identify, and that his crimes are believed to date to the 1970s.