BUFFALO, N.Y. (WKBW) — By definition, a pit bull is “an aggressive and tenacious person.”

Those words exactly describe Nick Simmons, and his mission to catch and expose those who may be trying to prey upon children on the internet.

“They do something called grooming,” Simmons said. “They groom the child.”

The Town of Tonawanda man is the founder of the YouTube channel Pitbulls vs. Predators. His main goal, he says, is to catch child sex predators by posing as an underage teen on dating apps like Tinder and Grindr.

“They’re everywhere,” he said of alleged predators. “It could be a lawyer, it could be a cop.”

Simmons says he doesn’t bait the person on the other end, but rather waits for them to contact him first. Using a decoy profile, he first tells the person who has contacted him that he “lied about my age.”

“One of the first things I say is, ‘just to let you know I lied about my age. I’m really 15.”

Simmons says sometimes, the person on the other end blocks the profile immediately. But other times, he says, “they’re all into it.”

Simmons has confronted six alleged predators so far. He says he always meets them in a public place, and says they’re shocked when he shows up with his cell phone camera.

In one confrontation captured on his phone, he asks a man if it was his first time meeting an underage teen through the internet. "Yes, actually it is,” the man replies.

“I’m shocked. I’m amazed that they’re here trying to pick up an underage kid,” Simmons says.

But Erie County District Attorney John Flynn says while there’s nothing technically illegal about what Simmons is doing, it raises some red flags from a law enforcement standpoint.

“He has no idea if there’s an active police investigation going on with this suspect or the person responding to the e-mails,” Flynn said. “This individual is putting his life in jeopardy by what he’s doing. That’s problem number one.”

Flynn says Simmons could also be putting an active police investigation in jeopardy.

“He’s fostering an element that we can’t have,” he said. “We just can’t have vigilantes out there.”

Simmons says he will cooperate with law enforcement at any time, and welcomes police to check out his channel.

His YouTube channel was shut down for a brief period last week by YouTube, after he said one of the alleged predators he confronted reported him for harassment. His channel is back up and running, and Simmons tells 7 Eyewitness News nothing and no one will stop him from exposing the truth.

“I just want to make sure that these predators are aware that there are people out there like me,” he said. “If you talk to an underage kid, you may get away with it a couple times, but you will eventually get caught, and meet me. Hopefully that’s where it stops.”

If you want to keep your children safe online, experts recommend you have a conversation with them about the realities of talking with strangers on the Internet. You can also click here to learn more about apps that may expose your child to child predators.

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