LANSING, Mich. (AP) – Two state regulators and a Flint employee are charged with evidence tampering and several other felony and misdemeanor counts related to the Michigan city’s lead-tainted water crisis.

The charges, filed Wednesday in a state court, stem from an investigation by the Michigan attorney general’s office.

Michael Prysby, a district engineer for the Michigan Department of Environmental Quality, and Stephen Busch, who is a supervisor with the DEQ’s Office of Drinking Water, are both charged with misconduct in office, conspiracy to tamper with evidence, tampering with evidence and violations of water treatment and monitoring laws.

Flint utilities administrator Michael Glasgow is charged with tampering with evidence for changing lead water-testing results and willful neglect of duty as a public servant.

For nearly 18 months after Flint’s water source was switched while the city was under state financial management, residents drank and bathed with improperly treated water that coursed through aging pipes and fixtures, releasing toxic lead.