The National Guard was patrolling the streets of Ferguson, MO last night but it hardly made a difference. Police came under "heavy fire" according to the State Highway Patrol as 31 people were arrested.

The Hill:

Protesters fired shots and hurled bottles at police, according to the St. Louis Post-Dispatch, and officers responded with sound cannons.

Multiple volleys of tear gas were also reported.

At least 31 people were arrested and at least two people were shot during the protests that extended into Tuesday morning, according to Captain Ron Johnson, who is leading the Missouri Highway Patrol's security presence there.

Johnson said no police officer fired a weapon Monday night, despite coming under what he called "heavy gunfire," according to reports. Johnson did not know the two victims’ conditions, but said police used armored vehicles to pick them up.

Johnson said some of those arrested were residents as far away as California and New York.

"I'm telling you, we're going to make this neighborhood whole," Johnson said, according to CNN. "And I am not going to let criminals that have come out here from across this country or live in this community define this neighborhood and define what we're going to do to make it right."

The violence came just hours after President Obama announced that Attorney General Eric Holder would travel to Ferguson as part of the Justice Department’s investigation into Michael Brown’s shooting.

Holder will meet with law enforcement and other officials.

Obama also plead for calm during remarks at the White House.

"While I understand the passions and the anger that arise over the death of Michael Brown, giving into that anger by looting or carrying guns, and even attacking the police, only deserves to raise tensions and stir chaos, it undermines, rather than advancing justice," Obama said.

Obama said most people in Ferguson were "peacefully protesting." But he warned the "small minority of individuals" who have been carrying guns, looting and attacking law enforcement officials "serves to raise tensions and stir chaos."

Holder on Monday asked for patience from the American public.

Holder said he was troubled by the “selective release” of information from other ongoing investigations of the shooting, which has touched off unrest and looting in the town.

What good - if any - Holder will do by bulling his way into the investigation is suspect. Missouri GOP Senator Roy Blount wants the Feds to take a back seat in the investigation:

I explained to the president that I've been pleased with my conversations with the attorney general and civil rights division regarding their helpful understanding that they aren't taking over this investigation, but are conducting a parallel review of the events that led to Michael Brown's death,” Blunt said in a statement.  

“I continue to believe that this is the best possible way to arrive at a transparent explanation that would be largely acceptable to all of those who have been impacted in the community by this tragedy,” he said.

Blunt has argued that state and local officials have a responsibility to delve into the matter on their own.

While the federal government has a role in assisting state officials, it should not take over their responsibilities, he said Monday.

While the Feds shadow the investigation by local officials, the riots continue. The violence appears to be escalating, despite the presence of troops. This mismanaged affair is spiraling toward a tragedy unless authorities can assert their authority and put the rioters and looters out of business.