A former regional Boy Scout official has been charged with sexually assaulting a 16-year-old Scout at least four times since July.

Charles Bickerstaff, 56, of Dixon, was charged with four counts of aggravated criminal sexual abuse and four counts of criminal sexual assault, Lee County Correctional Officer Larry Schremp said Sunday. Bail was set at $2.5 million at a hearing Friday, and Bickerstaff remained in custody Sunday.

Bickerstaff retired last year as district executive for the Blackhawk Area Council, covering northern Illinois and southern Wisconsin, of the Boy Scouts of America. He recruited and trained volunteers and helped organize fundraisers.

The boy alerted authorities to the alleged abuse in late April, and investigators discovered journals in Bickerstaff's house that detailed facts supporting the boy's account, Lee County Detective Sgt. David Glessner said.

Bickerstaff's day-to-day responsibilities did not involve contact with children, said Jim Pepper, district chairman for Lee, Ogle and Whiteside County District of the Blackhawk Area Council.

"I'm shocked and horrified by the prospect of this," Pepper said.

After Bickerstaff's arrest Thursday, scouting officials banned him from rejoining the program.

Authorities asked parents to speak to children who may have had contact with Bickerstaff.

"All we can do is pray that this is the only one, but I suspect we may get some phone calls," said Lee County State's Attorney Paul Whitcombe.

Jail officials said they did not know if Bickerstaff had a lawyer to speak for him. There was no immediate response to a call to Bickerstaff's home.