Obama Appears Wary About National Guard in Ferguson Obama calls for justice in Ferguson as grand jury could hear evidence Wednesday.

 -- President Obama appeared wary today about the National Guard being sent to Ferguson, Missouri, saying he urged the governor to ensure the troops were involved in a "limited" way.

Missouri Gov. Jay Nixon ordered the state's National Guard to be deployed to the city this morning after another violent night of clashes between protesters and police over the shooting death of Michael Brown on Aug. 9. Protesters have demanded that officer Darren Wilson be held accountable for shooting Brown.

The prosecutor's office in St. Louis County, which has jurisdiction in the case, said today a grand jury could begin hearing evidence against Wilson as soon as Wednesday to determine if he will be charged in the shooting.

Obama addressed the volatile situation in Ferguson for a second time in recent days and said he called Nixon about his decision to send in the Missouri National Guard.

"I spoke to Jay Nixon about this and expressed interest that if it was used, it would be in a limited and appropriate way," Obama said this afternoon. "He described the support role they’d be performing and I’ll be watching to see that it’s helping, not hindering, progress."

Obama also said Attorney General Eric Holder would travel to Ferguson Wednesday to meet with FBI and Department of Justice officials working the case. Holder said today there are more than 40 FBI investigators in Ferguson.

The state National Guard will arrive in Ferguson today to help protect the city's police command center during the protests, while the Missouri Highway Patrol continues to patrol the city.

Nixon order Guard's deployment this morning after protesters allegedly threw Molotov cocktails and fired gunshots at police Sunday night after the state-imposed curfew. Tonight there will be no curfew, Nixon said.

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The governor later issued a statement saying, "The Guard's immediate and limited responsibilities... are to provide protection, and ensure the safety of our Unified Command Center, which was the target last night of a coordinated attack."

Nixon said he signed the executive order after actions by violent protesters Sunday night included "the firing upon law enforcement officers, the shooting of a civilian, the throwing of Molotov cocktails, looting and a coordinated attempt to overrun the unified Command Center."

He said the Missouri State Highway Patrol and local police would remain in charge of policing the streets.

In addition, the governor said, "We will not use a curfew tonight."

Capt. Ron Johnson said today that he assured people that "protests will be allowed," but he added that he would not "allowed vandals to impact the safety of this community... or disrupt the soul of this community."

The police used tear gas Sunday night to clear protesters off the streets of the St. Louis suburb, action that police say was necessary because of shooting, looting and vandalism.

“When we saw violent acts … We had to act to protect lives and property,” Missouri State Highway Patrol Captain Ron Johnson said at an early-morning news conference.

The situation “took a very different turn after dark,” Johnson said, deteriorating at 8:25 p.m. with a civilian shooting. Protesters fired at police and threw Molotov cocktails, he said.

Sunday’s clashes continued more than a week’s worth of unrest in Ferguson after the Aug. 9 death of Brown, 18. Activists raised their hands, reflecting reports that Brown had his hands raised when the officer fired.

Police shouted over a bullhorn Sunday, warning the protesters.

They fired tear gas to clear the area.

Some people sprinted away from the gas.

Some protesters stood their ground, however, holding up signs as smoke surrounded them.

Sunday’s clashes come as a preliminary private autopsy shows Brown was shot at least six times, including twice in the head.

One of the bullets entered the top of Brown’s skull, meaning his head was bent forward, ABC News has confirmed. Brown was also shot four times in the right arm, the autopsy found.

The autopsy was performed Sunday at the request of Brown’s family.

Meanwhile, U.S. Attorney General Eric Holder ordered a federal medical examiner to perform a separate autopsy because of the circumstances surrounding the shooting.

The St. Louis County Medical Examiner's office has also conducted an autopsy which concluded that Brown died from gunshot wounds to the head and chest.

Schools in the Ferguson-Florissant School district will remain closed today because of lingering unrest in the area.

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