Families reached out to KQ2, Thursday night, concerned about a sex offender.
"Just really nervous, worried about my daughters. You know, having a 9-year-old and an 11-year-old that like playing out in the big backyard sometimes. We never had to worry about anything like that before," said Scott Hall.
Neighbors said 50-year-old Marc Widner moved into the neighborhood on August 1.
After a few months of living with his roommate and friends, neighbors found out Widner had a warrant for his arrest.
He failed to register as a sex offender in Buchanan County.
"I called the police myself and told other people in the neighborhood, that had children, that this is a big possibility this is true when we found it on the Internet. Then, everybody has been informed, and everybody called the police on their own," said Hall.
The Buchanan County Sheriff's Department arrested Widner late Thursday night.
They said they are glad the neighbors paid close attention and contacted them when they did.
"If it wasn't for the neighbors in the community contacting us and letting us know, he probably would've slipped through the system longer than what he did," said Kenneth Shryock.
Although the Buchanan County Sheriff's Department maintains the sex offender registry, there is a link on the Missouri State Highway Patrol's website, which is available for anyone.
"Even though they do live in our community, we will not tolerate them not following the rules, that they're required to, because of their conviction," said Sheriff Mike Strong.
Neighbors said they are delighted Widner is in custody, but more importantly, that their neighborhood can go back to the way it used to be.
Widner was charged with a Class B Felony, for failure to register as a sex offender.
Bond is set at $25,000.