The computer screen showed hundreds of dots on a map, each one indicating a sports betting app in use. One cluster of dots caught the investigator’s eye. He zoomed in and saw it was the athletic facilities at the University of Iowa.

The cluster was “one of those where once you see it, you can’t unsee it,” a source with knowledge of the map told ESPN.

The legal betting age in Iowa is 21, NCAA athletes and athletic staff aren’t allowed to gamble on NCAA-sanctioned sports, and only athletes and athletic staff had access to the facility. A high volume of activity there could be “indicative of some form of potential fraud, ID theft or something,” the source said.

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