(CNN) A Michigan judge issued a ruling Monday sending the criminal case of the state's Health and Human Services director to trial for the deaths of two men tied to the Flint water crisis, according to CNN affiliate WJRT-TV.

The men, who WJRT-TV identified as John Snyder and Robert Skidmore, both allegedly died of Legionnaires' disease after the city's water source was switched to the Flint River in 2014, which kicked off the water crisis. Eventually, 12 people died and more than 80 were sickened as a result of two waves of a deadly Legionnaires' disease outbreak in Flint.

Nick Lyon, the director, was charged last year with involuntary manslaughter, willful neglect of duty and misconduct in office for the deaths of the two men, WJRT-TV reports.

Court papers say Lyon is accused of "failing to alert the public about a Legionnaires' outbreak in Genesee County when he had noticed that another outbreak was foreseeable and ... conducting an investigation of the Legionnaires' outbreak in a grossly negligent manner."

Legionnaires' disease is a respiratory bacterial infection usually spread through mist that comes from a water source; it isn't spread person-to-person. Symptoms include fever, chills and a cough.

Read More