KANSAS CITY, Mo. (AP) — Kansas City plays a central role in a gang scheme that hires homeless people to cash counterfeit checks.

An Olathe, Kansas, convenience store manager was cleaning up his trash bins in October 2011 when he noticed a large amount of what appeared to be stolen mail.

The Kansas City Star reports that the resulting inquiry into mail thefts at 20 Johnson County, Kansas, businesses led to a national bank fraud investigation. About half of the 60 people prosecuted nationwide for hiring homeless people to pass counterfeit business checks have been charged in Kansas City and Springfield.

Assistant U.S. Attorney John Cowles says the scheme has cost Kansas City area banks about $1 million in recent years. He calculated the loss nationwide at more than $10 million.