Bill Schuette, Michigan’s attorney general, announced more criminal charges on Tuesday involved in the man-made water crisis in Flint.

In the 67th District Court, a judge approved new charges against two former emergency officials appointed by Governor Rick Snyder along with two former public works officials.

The two managers facing charges are Darnell Earley and Gerald Ambrose, and the city employees charged are Howard Croft and Daugherty Johnson.

Jeff Seipenko, an agent with the attorney general’s office, told the judge that the city employees conspired with both managers to change the water supply while fully knowing that the Flint Water Treatment Plant was “unable to produce safe water."

In pictures: Flint water crisis Show all 10 1 /10 In pictures: Flint water crisis In pictures: Flint water crisis Anthony Fordham picks up bottled water from the Food Bank of Eastern Michigan to deliver to a school after elevated lead levels were found in the city's water in Flint Reuters In pictures: Flint water crisis Michigan National Guard Staff Sergeant William Phillips (L) assists a Flint resident with bottled water at a fire station in Flint Reuters In pictures: Flint water crisis Flint residents Arthur Woodson, left, and Tony Palladino Jr. protest the arrival of Flint native and filmmaker Michael Moore as Moore accuses Gov.Rick Snyder of poisoning Flint water during a rally outside of city hall in Flint AP In pictures: Flint water crisis Flint residents pick up bottled water and water filters at a fire station in Flint. Michigan National Guard members were set to arrive in Flint to join door-to-door efforts to distribute bottled water and other supplies to residents coping with the city's crisis over lead-contaminated drinking water Reuters In pictures: Flint water crisis Soldiers from the Michigan Army National Guard Flint prepare to give Flint residents bottled water at a fire station in Flint Getty Images In pictures: Flint water crisis Justin Roberson (L), age 6, of Flint, Michigan and Mychal Adams, age 1, of Flint wait on a stack of bottled water at a rally where the Rev. Jesse Jackson was speaking about about the water crises at the Heavenly Host Baptist Church in Flint Getty Images In pictures: Flint water crisis A man sits next to a stack of bottled water at the Heavenly Host Baptist Church in Flint 2016 Getty Images In pictures: Flint water crisis The top of a water tower is seen at the Flint Water Plant. President Barack Obama declared a state of emergency in Michigan and ordered federal aid to be used to help state and local response efforts to an area affected by contaminated water Reuters In pictures: Flint water crisis Rosie Wright, center, rallies with the crowd over Flint's water crisis in Ann Arbor, Michigan AP In pictures: Flint water crisis Rick Catherman participates in a rally around Flint's water crisis in Ann Arbor, Michigan AP

So far, 13 people —12 current or former state employees—have been charged in the lead contamination of Flint’s water system and the outbreak of Legionnaires’ disease across the city.