It was not clear what specific charges will be leveled on former Michigan Gov. Rick Snyder, his health director Nick Lyon and other administration officials. Defense lawyers have been notified and were told to expect initial court appearances soon.
Snyder’s attorney didn’t return calls seeking comment.
The water scandal put Flint, a majority Black city, in the national spotlight. Snyder, a Republican, had been in office two years when the state-appointed managers in the city switched Flint's water supply to the Flint River in 2014 as a cost-saving measure while a pipeline was being built to Lake Huron.
Residents immediately began complaining of health issues, including hair loss and rashes. In 2015, doctors found dangerous levels of lead in the blood of children and urged the city to stop using water from the river.
The water wasn't treated to reduce corrosion, causing lead from old pipes to reach the distribution system used by residents. Many were forced to resort to bottled water.
The crisis led some to accuse officials of racism.
At the same time, bacteria in the water was blamed for an outbreak of Legionnaires’ disease in 2014-15. The outbreak caused several deaths and reports of illness. Legionella bacteria can emerge through misting and cooling systems, triggering a severe form of pneumonia, especially in people with weakened immune systems. Authorities counted at least 90 cases in Genesee County, including 12 deaths.
Snyder announced the outbreak in January 2016, but Lyon said he knew of cases reported months earlier.
The state eventually settled with victims for $500 million after dozens of lawsuits were filed.
The Associated Press contributed to this report.