MIAMI (AP) — For the first time in history, federal health officials said Friday they will ban certain types of Medicare and Medicaid providers in three high-fraud cities from enrolling in the tax-payer funded programs for the poor as part of an effort to prevent scams.

The strict moratoriums, which start Tuesday, give federal health officials unprecedented power to choose any region and industry with high fraud activity and ban new Medicare and Medicaid providers from joining the programs for six months.

The administrator of the Centers for Medicare and Medicaid Services said the agency is targeting providers of home health care in eight counties in the Miami and Chicago areas. All ambulance providers would be banned in eight counties in the Houston area.