GRAND RAPIDS, Mich. (WOOD) — A former substitute teacher from metro Grand Rapids has been charged with four felonies after admitting to asking someone he believed to be an underaged girl to send him explicit photos, court documents show.

Brett Wardrop, 50, was arraigned Tuesday on charges of child sexually abusive activity, two counts of using a computer to commit a crime and a count of accosting a child for immoral purposes. The most serious charge is a 20-year felony. Bond was set at $20,000.

In court documents filed Monday, a detective wrote that the Kent County Sheriff’s Department started investigating Wardrop after being contacted by the person who was pretending to be a 14-year-old girl online to try to identify predators. That person had met Wardrop on an app called Whisper, where their conversations became “inappropriate.”

On Monday, detectives arrested Wardrop outside his home north of Grand Rapids. When he was questioned, the court documents said, he told detectives he had asked the person who he thought was a teen girl in Indiana for explicit photos and that he had explicit conversations with her.

Wardrop said he messaged with the girl on his cellphone during class while working as a substitute teacher, the court documents said.

He said he had similar conversations with between 10 and 30 other teen girls and that he had gotten nude pictures from some of them.

News 8 asked Kent County Prosecutor Chris Becker whether Wardrop will be charged for past crimes.

“Just because somebody says something, that’s not necessarily enough to charge,” Becker said. “We have to show a crime is independent of what somebody said. So right now, we’ll see what the investigation turns up. If they get a hold of his computers, we can revisit that. But as of this point in time, we’ve charged with him with what evidence we can charge him with right now.”

The sheriff’s office said it’s still investigating Wardrop and working to identify victims. Anyone with information is asked to call investigators at 616.632.6125 or Silent Observer at 616.774.2345.

ABUSE SURVIVOR TIPPED OFF INVESTIGATORS

Samantha Lawrence, a survivor of child abuse who lives in Indiana, pointed deputies toward Wardrop. She said she pursuing online predators last month.

“This means more than anything to me right now,” Lawrence told News 8. “This has stirred up something in me.”

It was her adult daughter who impersonated a teen girl on Whisper.

“We put decoys in chat rooms that are on dating apps,” she said. “We put decoys in there who are adults that pose as children. All we do is make the profile and set it up there and leave it alone.”

She said Wardrop started messaging her daughter’s fake profile in mid-March.

“He thought he was talking to a real 14-year-old girl,” Lawrence said. “We make sure to let them know, ‘Hey, we’re underage.’ We do that multiple times. We gave them a chance to say, ‘No, nevermind.’”

In the conversations with the decoy, Wardrop kept asking the female for nude photos, according to court documents.

“He was super graphic,” Lawrence said. “Like super graphic with her. We would ask him questions trying to find out information, but he was super careful. We knew this was something he had done before.”

She told law enforcement about the situation on March 18, sending them screenshots and screen recordings. She didn’t know his real name, only his username. She said detectives told her to continue the conversation with Wardrop until they discovered his identity, which they did a few days later.

“He was an educator,” Lawrence said. “He was standing in front of our kids. I knew there was more than just this decoy to him.”

The sheriff’s office said Wardrop had worked in “multiple local school districts.” In court Tuesday, Wardrop said he was no longer employed by substitute teacher provider Edustaff.

Superintendent Scott Smith confirmed to News 8 that Wardrop substituted at Cedar Springs Public Schools. He said when the district learned about the accusations against Wardrop, leaders blocked him from teaching in the district again.

Lawrence has grandchildren now, and that’s part of what influences her to stop abuse from happening to anyone else.

“It drives me, the thing that some of these men say,” Lawrence said. “The photos that they send you are sometimes unbearable. But it’s worth it. Especially in moments like this.

She said she’s trying to catch several other predators.

“We have a few,” she said. “Quite a few. They’re not in short demand at all. It’s a lot worse than any person could ever imagine, it’s like that times a million.”