By Howard Monroe

BUCKS COUNTY, Pa. (CBS) — Bucks County authorities have arrested three men for sexually assaulting young boys. The district attorney says two of those men assaulted the same boy.

One of the suspects is accused of assaulting his foster child. The DA also says he was a bus driver and was involved in youth sports.

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Some of these abuses went on for years and authorities fear more victims may be out there.

“I’ve seen this more than once. I can’t explain the phenomenon, but sometimes when a young person becomes abused in the first instance, they become more susceptible to future abuse,” Bucks County District Attorney Matt Weintraub said.

Weintraub announced sexual assault charges against three men.

Credit: CBS3

John Evans, of Tullytown, was arrested Tuesday. The DA says he assaulted two boys over the course of three-and-a-half years, beginning in January 2017 and ending just this month when the foster child came forward.

According to court documents, the 40-year-old started assaulting the then-16-year-old shortly after he was placed in his care. Evans was arrested after the victim came forward.

“These three defendants are off the street today because of the bravery of the victims they abused,” Weintraub said.

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Charles Hoffman, of Bristol Township, was arrested Wednesday and is charged with assaulting one boy. It’s the same boy who the DA says was assaulted by 57-year-old Louis Aiello, of Penndel.

Aiello was arrested Tuesday at his home on the 400 block of Rumpf Avenue. He was charged with assaulting two boys.

The DA says Aiello sexually assaulted one of his victims from 2001 to 2007, beginning when the boy was just 11 or 12 years old.

That victim was as young as 5 when authorities say he was assaulted by Hoffman beginning in 1995.

Both Hoffman and Aiello were friends of the victim’s family, but the DA says it’s not clear if they know each other.

“Let us investigate, let us run these down so we can protect kids because that is what we are sworn to do,” Weintraub said.

Regarding Evans, CBS3 reached out to the county’s Department of Children and Youth to figure out how many children he’s fostered. We’re waiting to hear back.

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If you suspect child abuse, you can contact PA Childline at 1-800-932-0313 or www.keepkidssafe.pa.gov