JOLIET, Ill. (CBS) — Bond was set at $250,000 on Wednesday for a suburban children’s counselor and high school referee accused of using the Internet to try to arrange sex with someone he thought was a 13-year-old girl.

John Martynus is a husband, a mental health counselor for children, and has been a high school referee for decades. CBS 2’s Dana Kozlov reports that his family and neighbors didn’t have a clue that anything might be wrong.

“He seemed like, just what little I’d known of him, was just an average guy,” said Plainfield resident Kevin Casey, a father of four who lives next door to Martynus.

Casey said that, until Wednesday, he hadn’t heard about his neighbor’s arrest on Monday for allegedly trying to have sex with a 13 year old girl who turned out to be a cop.

“My daughter, she walks home from school. She goes to a high school right down the street,” Casey said. “She stays home by herself periodically, you know, we’re running errands. And it’s scary to know that this person may or may not be right next door.”

Until his arrest, Martynus worked with kids as a mental health counselor for the Will County Health Department. He also spent 22 years as a high school basketball referee. Not anymore.

Martynus’ attorney Donald DeWilkins said, “My understanding is, from speaking with the family, that they’ve decided to put him on administrative leave and they’re going to attempt to terminate him.”

Investigators arrested Martynus Monday night at a Crete parking lot, where he had arranged to meet the undercover officer whom he believed was a 13-year-old girl.

Prosecutors said the undercover officer had communicated with Martynus over the weekend.

Crete Police Chief James Paoletti called Martynus’ messages aggressive and explicit.

DeWilkins said Martynus’ family was “stunned” by the allegations.

“The gentleman’s never had any prior criminal history, no allegations, anything of that nature,” DeWilkins said.

In a statement Wednesday afternoon, a Will County Health Department spokesperson said, “The safety and well-being of people who utilize the Will County Health Department programs and services are always our priority. We are fully cooperating with the current investigation.”

Martynus was also suspended immediately and indefinitely as an Illinois High School Association referee.

Investigators said Tuesday that they are looking into the possibility there are more, actual, young victims.

Will County State’s Attorney Charles Pelkie said, “It is an ongoing investigation. But beyond that, I really can’t comment.”

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