DODGE CENTER, Minn. — A Dodge Center man was arrested after a vigilante group set up a sting and then called the sheriff and accused the man of soliciting a 14-year-old boy for sex. There was, however, no 14-year-old boy. The vigilantes, calling themselves the Midwest Predators Catchers, had posed online as a minor on the hook-up site Grindr as a lure. After they alerted the sheriff’s office that they had trapped Joseph Lee Carlson, 30, in the city’s North Park, deputies made the arrest. This was abut 6:30 p.m. Carlson was not a stranger to investigators. He had been under investigation in August by U.S. Homeland Security Department and Dodge County authorities, said Sheriff Scott Rose. Carlson had told investigators that he thought that he was chatting online with an 18-year-old pretending to be a minor and that he would have turned him away if he knew he truly a juvenile. Indeed Grindr has loose protocols to keep minors off the site. Carlson said also that he had reason tp believe his phone had been hacked. In the end the investigators concluded that there was no sign of unusual activity on Carlson’s phone, Rose said. But after the North Park sting set up by Midwest Predator Catchers, Carlson was arrested. He now faces 10 charges of possession of child pornography and three charges of soliciting a minor. According to the criminal complaint, the August search of Carlson’s home yielded 47 images and 155 videos of child pornography. There were no indications that Carlson produced any of the images, although, the complaint said, there were 529 chats in which Carlson chatted lewdly online with juveniles, both boys and girls. In some exchanges Carlson appeared to post images of his own genitals in what could be inferred easily to be hook-up bids.