With the possibility of further clashes in Ferguson hinging on the imminent decision from a grand jury, Missouri Gov. Jay Nixon issued a stern warning Tuesday afternoon: If the police are unable to control protests in the St. Louis area, then the National Guard will.

Nixon and St. Louis law enforcement are preparing for a grand jury decision that could reignite smoldering unrest in Ferguson, on the outskirts of St. Louis. Later this month a St. Louis County grand jury is expected to rule on whether police officer Darren Wilson should be prosecuted for the Aug. 9 shooting death of Michael Brown, an unarmed African-American 18-year-old. If Wilson is not prosecuted for the shooting, which ignited sometimes violent protests, many see further demonstrations as all but inevitable.

“The National Guard has been and will continue to be part of our contingency planning,” Nixon said Tuesday at a news conference. “The guard will be available when we determine it is necessary to support local law enforcement.”

He emphasized community outreach as an important component of the preparations for demonstrations. Local community groups, including the St. Louis County NAACP, have been meeting with the police to ensure the safety of protesters.

“Over the past few months, I’ve heard from people of good faith on all sides of these issues,” Nixon said. “And what unites them all is a desire for peace and progress. They know, as I do, that for real progress to take root in our hearts, our minds and our laws, peace must prevail.”

In addition to marshaling the National Guard and enlisting the assistance of community members, state and local officials have provided more than 1,000 law enforcement officers with thousands of hours in training, according to the governor’s office. Fire and emergency medical services will also be at the ready in the event of new unrest.

In a statement released ahead of Nixon’s news conference, a group of Missouri protesters blamed the majority of the violence in Ferguson on local law enforcement.

“We have proven we can peacefully assemble and function at a protest,” said community organizer Damon Davis in the statement. “Can the police say the same?”

Amnesty International has accused local police of committing rights abuses, such as excessive use of tear gas and interfering with journalists, during the height of the Ferguson protests.