Sickening moment predator hunters confront 57-year-old man they claim tried to meet up with 13-year-old girl

A man was arrested after being confronted by an online child predator hunter ahead of what he thought was a meetup with an underage girl.

A video shows Sean Brennan, 57, batting back the claims at his job in Wyoming Friday - before getting fired by his boss and booked into the local jail later that day.

It shows him coming face-to-face with Tommy Fellows, a member of Colorado Ped Patrol, at Brennan's place of work in Lander.

Throughout the clip, Fellows clutches and repeatedly references a binder he says contains a transcript of conversations between Brennan and decoy 'girls' - one of whom was allegedly 13.

During the altercation, Fellows accuses Brennan of teaching one of the made-up girls sex acts, and of making plans with her for the day. He also said he sent him and colleagues sexual pictures.

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'I have a little incident of a couple girls you've been talking to on the internet,' Fellows tells Brennan in the footage, after entering the Shirts and More store where he works.   

Brennan, under the impression the watchdog was a potential customer, had first offered his assistance.

'Do you get sexual with them?' Fellows goes on to ask, leading the two men to walk outside together out of earshot of others inside.

'No,' responds Brennan, who by the end of the filmed altercation is seen conversing with several cops. 'I let them know off the bat.'

Fellows, however, proceeds to press the man further, citing correspondence sent between Brennan and his colleagues before the meet.   

'So you'd never send, like, inappropriate pictures or anything like that?' he asks at a point - to which Brennan replies, 'Nope.'

'So that phone on you has no child porn on it or anything like that?' Fellows asks - leading to another 'Nope' from the man in question.

At this point, Fellows produces the binder saying he could prove otherwise - and asks the suspect if the police would rather come check.

Flipping through its pages, he tells Brennan: 'I have three of these books, right? Three different children.'

'Do you beg minors for naked pictures often?' he asks, before referencing a specific alleged exchange where he allegedly got angry after not receiving a photo from one of the made-up minors.

'You said, "Send me a picture" and you got pissed off,' he says outside the man's place of work. 

'Then you said, "Listen little girl, just remember, I'm not mad, but don't ever ask me for a picture again.'

At another point in, Fellows brings up how Brennan was convicted of a child pornography crime in Arizona around 25 years ago, after which he had to register as a sex offender.

But Brennan responds by claiming that status did not carry over when he moved to Wyoming, because local officials told him his conviction was 'crap' by their standards, he said.

He goes on to claim he was only convicted after doing research on a public library computer about what nude beach to visit with his then girlfriend. He said it was images of underage girls on some of these sites that got him charged.

At this point, Brennan's boss emerges, confused about the commotion. 

'I’m probably going to get canned now,' Brennan tells Fellows at the point - a prediction that would pan out in a matter if minutes.

The clip shows the business owner, identified as Daniel Carey, conveying disgust and concern about the situation.

At a point, he produces Brennan's job application - which, as he suspected, did not show any prior convictions.

He reportedly responded by firing Brennan that day, Cowboy State Daily reported - revealing how Caret told them how Brennan was on his phone often and struggled to focus at the job.

'This was so far from what my company would even consider,' he told the outlet. 'He was pretty, I don’t know what the word is, good at hiding it, to say the least. Truly stunning that he’d been doing this and I had no clue.'   

After several minutes, Lander Police respond to the scene, with one officer heard remarking how 'Wyoming is way behind Colorado' in the strength of its sex-crime laws and how it would be unlikely they could make a felony arrest at this point.

The video ends with officers discussing a need to investigate further. Off-screen, officers were able to make an arrest that day, with Brennan booked into the Fremont County Detention Center Friday, Cowboy State Daily reported.

Court documents were not available because of state laws limiting public exposure of sex cases at preliminary stages, as is the case here.