FLINT, Mich. (AP) – A special prosecutor says the head of Michigan’s health department could be hit with additional charges in the Flint water investigation.

Nick Lyon is charged with involuntary manslaughter in the death of a man who had Legionnaires’ disease. Lyon is accused of covering up news of the outbreak in 2014 and 2015.

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Special prosecutor Todd Flood told a judge Thursday that he might seek additional charges, depending on test results. He says he needs to “ferret that out.”

Lyon is director of the Health and Human Services Department. He’s pleaded not guilty. His lawyers want the case to move quickly.

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Lyon became the highest-ranking member of Gov. Rick Snyder’s administration to be snagged in a criminal investigation of how Flint’s water system became poisoned after officials tapped the Flint River in 2014.

Michigan’s chief medical officer, Dr. Eden Wells, is charged with obstruction of justice. Rich Baird, an adviser to Gov. Rick Snyder, told state employees that the charges are an “incredible overreach.”

 

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(© Copyright 2017 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)