BUTLER COUNTY, Ohio -- Authorities said an illegal immigrant went into the Butler County Sheriff's Department looking to get a background check.

The staff at the sheriff's office noticed something about the ID that set off a red flag, and helped authorities bust the largest fake I-D case in the state of Ohio.

Sheriff Richard Jones said investigators they found the business and 4,000 blank ID cards just feet away from the Butler County Jail.

The cards were going for $100 to $200 a piece.

The sheriff said the blank cards were being turned into Ohio driver's licenses, Mexican driver's licenses, and green cards.

Authorities said they arrested three people who face 18 charges in connection with allegedly making the fake I-D's.