Engineer Michael Prysby stands by as his defense attorney Richard Hillman, right, enters a not guilty plea at arraignment Wednesday.

FLINT, Mich. — The Flint water crisis has become a criminal case, with two state regulators and a city employee charged with official misconduct, evidence-tampering and other offenses over the lead contamination that alarmed the country and brought cries of racism.

For nearly 18 months, the poor, majority-black city of 100,000 used the Flint River for tap water as a way to save money — a decision made by a state-appointed emergency manager — while a new pipeline was under construction. But the water wasn't treated to control corrosion. The result: Lead was released from aging pipes and fixtures as water flowed into homes and businesses.

“This is a road back to restoring faith and confidence in all Michigan families in their government,” state Attorney General Bill Schuette said Wednesday in announcing the first charges to come out of the disaster, blamed on a series of bad decisions by bureaucrats and political leaders. He warned there will be more charges — “That I can guarantee” — and added: “No one is off the table.”

Gov. Rick Snyder didn't acknowledge the problem until last fall, when tests revealed high levels of lead in children, in whom the heavy metal can cause low IQs.

Michael Prysby, a former district engineer with the state Department of Environmental Quality, and Stephen Busch, a supervisor in the department's drinking water office, were charged with misconduct, conspiracy, tampering with test results and misdemeanor violations of clean-water law.

Among other things, they were accused of failing to order anticorrosion chemicals added to the water to coat the pipes and prevent them from releasing lead.

Flint utilities administrator Michael Glasgow, who oversaw day-to-day operations at the city's water plant at the time, also was charged with tampering with evidence for allegedly falsifying test results and with willful neglect of duty.