Six Michigan employees were charged Friday with misconduct in office for their alleged roles in the lead contamination of Flint’s water supply, which has exposed thousands of children to the toxin and left most city residents drinking bottled water for more than two years.

Attorney General Bill Schuette filed the charges against three employees of the state’s Department of Health and Human Services and three others from the state Department of Environmental Quality, including the former chief of Michigan’s Office of Drinking Water and Municipal Assistance.

The filings bring the number of government workers accused in the water crisis to nine. Schuette, who is overseeing the probe, filed charges in April against two other Department of Environmental Quality workers and a Flint water quality supervisor. He also filed civil charges in June against two engineering firms that allegedly “botched” their work on the water supply system, contributing to the crisis.

“These individuals concealed the truth,” Schuette said at a morning news conference. “They were criminally wrong to do so. And the victims, these are real people, who have been lied to by government officials and been treated as if they don’t count.”

The disaster in the once-thriving industrial city of about 95,000 began in early 2014. For decades, it had used water piped in from Lake Huron, with anti-corrosion chemicals added along the way by Detroit water officials.

Then in April 2014, with the city under the control of an emergency manager appointed by Gov. Rick Snyder, officials switched to Flint River water to save money. But the state’s environmental quality agency failed to ensure that corrosion-control additives were part of the new water supply, which allowed lead and other substances such as iron to leach from aging pipes.

Flint switched back to its previous water source last fall, but most people are still drinking bottled water.

The Health and Human Services employees-Nancy Peeler, Robert Scott and Corrine Miller-all face charges of misconduct in office, conspiring to commit misconduct in office and willful neglect of duty, according to Schuette. They allegedly hid or disregarded test results that showed high lead levels in Flint residents’ blood.

An investigator from Schuette’s office said in court Friday morning that Peeler and Scott, who work in the department’s program to prevent lead poisoning in children, conspired with others “to effectively bury” a report from an epidemiologist that warranted more investigation, according to the Detroit News. Miller, the state’s head epidemiologist, allegedly ordered a department employee to ignore the findings of high lead levels and take no action.

Shekter Smith, the former top drinking water official, and current officials Patrick Cook and Adam Rosenthal were charged with misconduct in office related to federal regulations that limit lead in drinking water.