Calls for Michigan Governor Rick Snyder’s ouster—and arrest—are growing after internal emails showed that his high-level staffers were aware of lead poisoning in Flint’s public water supply six months before the administration declared a state of emergency.

According to the newly-released emails, which were obtained by NBC News, Snyder’s chief of staff at the time, Dennis Muchmore, wrote to an unnamed high-level health department staffer: “I’m frustrated by the water issue in Flint.”

“These folks are scared and worried about the health impacts and they are basically getting blown off by us (as a state we’re just not sympathizing with their plight),” Muchmore wrote in the email, according to journalists Stephanie Gosk, Kevin Monahan, Tim Sandler and Hannah Rappleye.

“I really don’t think people are getting the benefit of the doubt,” wrote Muchmore. “Now they are concerned and rightfully so about the lead level studies they are receiving.”

But it was not until this week that Snyder declared a state of emergency, following in the footsteps of the city’s mayor. “The health and welfare of Flint residents is a top priority and we’re committed to a coordinated approach with resources from state agencies to address all aspects of this situation,” Snyder said on Tuesday.

Following the resignation of Michigan’s top environmental official, as well as sustained community demands, the Department of Justice announced this week it is launching an investigation into the water crisis.

Many hold Snyder directly culpable for the emergency itself, and note his role in the Detroit water crisis.

“The source of the Flint Water Crisis leads directly to Gov. Rick Snyder and the fiscal austerity policies that he and his Republican colleagues have been pushing for years on Michigan residents,” said Lonnie Scott, executive director of Progress Michigan,” in a statement released Thursday. “Families in Flint were forced to drink lead-tainted water while the administration scoffed at their concerns and cries for help. An entire generation of Michiganders now face an uncertain future because of Republican cuts to essential and life-giving services.”