FLINT, Mich. (AP) — An official with the Karegnondi Water Authority says some of the agency’s records have been subpoenaed by state and county prosecutors who are investigating Flint’s water crisis.

Jeff Wright, Genesee County Drain Commissioner and Karegnondi Water Authority CEO, says the offices of Attorney General Bill Schuette and Genesee County Prosecutor David Leyton issued the subpoena in a search for records detailing the decision-making process that led to Flint’s water troubles.

He tells The Flint Journal that the subpoenas sought documents detailing the city’s switch to the Flint River as its drinking water source and the city’s decision to join the Karegnondi Water Authority.

Schuette’s office has charged two state Department of Environmental Quality employees and a Flint water plant employee.

Schuette has said it’s likely that more charges will come as the investigation continues.