A federal prosecutor from Massachusetts is joining Michigan's attorney general to announce a "new development" in state and federal probes of a company that sold steroid injection materials linked to a fungal meningitis outbreak.

Michigan Attorney General Bill Schuette says he and Boston U.S. Attorney Carmen Ortiz plan a news conference Monday morning in Detroit. Schuette says they'll discuss a "new development in the independent state and federal investigations of New England Compounding Center."

Investigations began more than a year ago. The Michigan appeals court in April approved a request for a grand jury.

The Massachusetts company's steroid materials have been linked to 751 meningitis and other infections nationwide, including 264 in Michigan.