CHICAGO (CBS) -- There are bad first dates and then there's what happened to Zach Keil.
Keil agreed to meet a man Monday after chatting with him on Grindr, where he sent Keil a photo.
"He had said that he was staying at this hotel," Keil said. "He was like, 'do you want to come hang out.' I was like. 'yeah, that sounds cool.'"
Keil says near the hotel he saw the man he was going to meet wearing a wig and wielding what looked like a gun. Keil said the man told him to give him his money.
"I was like, 'I only have like $23 on me,'" Keil said. "He was like, 'give it to me.'"
Keil says the man took his money and his bike. The next day, he says he realized the robber was still active on Grindr. So, he called the detective on his case to suggest making a fake profile on the app.
Schererville police took the advice and now, if he wants it, Jacob Trosper has a new profile picture -- his mug shot.
With the help of an ATF agent, police arranged a meeting with Trosper on Tuesday.
Investigators say he approached an unmarked car with the same wig on and tried to open the door.
Police arrested him and found a BB gun shaped like a handgun in his waistband.
"It just felt good to do something to help get somebody off the streets who wasn't a good person," Keil said.
Trosper was charged in December for allegedly robbing another man he'd set up a meeting with.
He should have been behind bars when this week's robbery happened, but while out on work release, he didn't go back to jail.
As for Keil, police found and returned his bike.
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