CHICAGO (AP) — A nationwide health care fraud sweep that led to charges against hundreds of doctors, nurses and pharmacy owners includes four cases being prosecuted in Chicago.

The 13 Illinois defendants include a Chicago dermatologist accused of fraudulent billing and seven employees of home health care companies.

The federal government imposed a first-of-its-kind moratorium on enrollment of new home health providers in the metropolitan Chicago area in 2013.

Prosecutors in the U.S. District Court’s Northern District of Illinois announced the crackdown results Thursday as part of a cross-country dragnet involving allegedly fraudulent billings of Medicare and Medicaid totaling more than $700 million.

The U.S. attorney for southern Illinois has scheduled an afternoon news conference in Fairview Heights to outline additional cases.

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