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

"This is a road back to restoring faith and confidence in all Michigan families in their government," Michigan Attorney General Bill Schuette said in announcing the charges, months after officials conceded a series of bad decisions caused the disaster.

He warned there will be more charges - "That I can guarantee" - and added: "No one is off the table."

Genesee County Prosecutor David Leyton, who is conducting a parallel investigation, said at the same news conference that he expected to file charges stemming from his probe.

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For nearly 18 months, the poor, mostly 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.

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 and behavioral problems.

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. The felonies carry maximum penalties of four to five years in prison.

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 Wednesday with tampering with evidence for allegedly falsifying lead water-testing results and with willful neglect of duty.

Essentially, all three were accused of failing to do their duty to provide safe drinking water.

Busch and Prysby were immediately suspended without pay. Glasgow was also placed on leave. Prysby did not return a message seeking comment. Telephone numbers for the others could not be found. It wasn't known if they have lawyers.

"They failed Michigan families. Indeed, they failed us all," Schuette said. "I don't care where you live."

"It causes me anger. It causes me despair. I think it causes most people anger and despair," Schuette told CBS News correspondent Dean Reynolds.

Ellis Stafford, one of the investigators, is a Flint native.

"It really does hurt. It really hurts when I have friends, personal close friends," Stafford told Reynolds through tears. "They live here."

U.S. Rep. Dan Kildee, D-Michigan, praised Wednesday's development.

"Today's criminal charges are one step to bringing justice to Flint families who are the victims of this terrible tragedy," Kildee said in a statement.

The crisis - and state officials' slow and dismissive response to complaints about the water from experts and Flint residents - led to allegations of environmental racism, emerged as an issue in the presidential race during Michigan's Democratic primary in March, and sent other cities around the U.S. rushing to test their water, particularly in older neighborhoods that still use lead pipes.

For months, people in Flint have been relying on filters and bottled water. Some still do not trust what comes out of their taps, even though the city rejoined the Detroit-area water system last fall and anticorrosive phosphates are being added to the water.

The governor filled a few jugs of filtered Flint tap water this week and pledged to drink it for 30 days to show it's safe.

"It's a good first step, but it's a small step," Flint resident Melissa Mays said of the criminal charges. "These are lower-level people, and I want to know who was instructing them to do what they did. I think it's important that we can see some form of accountability being laid out, but at the end of the day we still can't drink or bathe in our water safely."

Mays told Reynolds how her children reacted to news of the charges.

"Their first question was, 'Is it Gov. Snyder?' And I said, 'No, he's not on the list,' and they said, 'Not enough,'" Mays said.

Outside experts have also suggested a link between the river and a deadly Legionnaires' disease outbreak. There were at least 91 cases, including 12 deaths, across Genesee County, which contains Flint, during a 17-month period. That represents a five-fold increase over what the county averaged before.

After the crisis broke open, DEQ Director Dan Wyant and his spokesman resigned. The chief of the department's drinking water office was fired. And the director of the U.S. Environmental Protection Agency's Chicago-based Midwest office stepped down.

The Flint debacle exposed a problem that extends well beyond the one-time industrial powerhouse.

An Associated Press analysis of EPA data found that nearly 1,400 water systems serving 3.6 million Americans exceeded the federal lead standard at least once between the beginning of 2013 and last September.

Most U.S. cities stopped installing lead pipes in the 1930s to carry water from main lines under the streets and into homes. But a survey by the American Water Works Association found that 6.5 million of these pipes are still in use.

Some researchers question whether chemical treatment and routine testing for lead in the water are enough, arguing that the only way to remove the threat is to replace the pipes. But the cost could easily be hundreds of millions of dollars or more.