For 63 consecutive nights, deputies from the U.S. Marshals Service in Portland, Oregon, have stood their ground, carrying out their mission to protect and defend the federal courthouse from violent agitators.

In an exclusive interview with NBC News Correspondent Erin McLaughlin, people running the U.S. Marshals Service reflected on the Portland protests — meant to shine a light on racial inequality and police use of force in the wake of George Floyd’s death — that take on a different tone after the sun goes down by groups intent on causing destruction and mayhem with seemingly little regard for justice.

“I think that we’re at a watershed moment in history in America,” said Russel E. Burger, the U.S. Marshal for Oregon. “What we’re facing each night has been very difficult for our personnel to manage. We want to protect the first amendment right of people to express their views. But at the same time, we have to protect the federal judicial process, this facility and the people inside it.”

The Marshals Service is tasked with securing the Mark O. Hatfield Federal Courthouse in downtown Portland, the interior as well as the judges and court personnel who work there. During the July 4th weekend, when federal agents arrived to protect the courthouse on a full time basis, it became ground zero for a nightly battle between protestors and law enforcement.

Burger said his deputies have taken a defensive posture from inside the building, only coming outside to respond to attempts to breach the entrance or when protestors have set fire to the building. And he says two months of demonstrations have taken its toll on the men and women who work for him.

“They live in this community. They go to church here, all their friends and family are here. And so night after night to come under attack is, is very stressful for them,” Burger said. “In addition to that the people that have come in from around the country to augment our forces, they’re away from their families.”

After that July 4th weekend, the courthouse was boarded up, a fence built around the perimeter for extra reinforcements. Since then, the attacks from over the fence with projectiles have been relentless.

NBC News got a firsthand look at some of those weapons.

Bricks, batteries, frozen water bottles, sling shots with ball bearings, feces, urine, bleach and canned goods have been launched over the fence at deputies.

Professional fireworks and mortar rounds stuffed with nails are lit and fired at them, like IED’s in a war zone.

Hockey sticks embedded with nails have been placed under the tires of government vehicles.

At least 20 deputy marshals have been injured, which include lacerations, concussions, a dislocated shoulder, and one deputy attacked with a hammer. Three are still waiting to see if they have permanent eye damage from lasers pointed at them by protestors.

So far, more than 50 people face federal charges in connection with the riots.

The deployment of federal agents dressed in military fatigues seen on video detaining and transporting protestors in unmarked vans several weeks ago triggered even more social unrest in a city already at a heightened state of emergency. The Marshals Service maintains none of their personnel were out in the streets making random arrests, only dealing with incidents at the courthouse and on federal property.

Nonetheless, the Director of the U.S. Marshals Service, Donald W. Washington, says his agency has been caught in the middle, trying to deescalate the tension with peaceful protestors exercising their right to free speech while coming under attack by a smaller but more violent anti-police faction.

“The last thing that that our officers want to do is to face off against an American citizen,” Washington said. “I don’t think that the legitimate protesters, those who are freely complaining about and bringing their grievances about what has happened since George Floyd, I don’t think it’s them. I do not believe that that is the case. But there is an element there.”

Burger says the attacks are coordinated, rioters using portable radios and communicating with encrypted messaging on cellphones. He says it usually begins around midnight with a hard corps group of 250 to 300 violent opportunists as he describes them, who have stayed behind after the peaceful protestors have gone home.

According to Burger, militant movements and groups with a strong presence in the Northwest, like Antifa and the Pacific Northwest Youth Liberation Front are behind the late night attacks.

Marshals and other law enforcement agencies have been criticized for their use of tear gas and other irritants on protestors, but say they’re left with little choice when they have to leave the courthouse to confront the rioters.

“In order to address the problem that they’re faced with while being under attack, they have to defend themselves and they can’t do hand-to-hand combat,” Burger said. “They have to use the chemical munitions, and they don’t use those unless they have to.”

The Marshals Service has acknowledged at least two cases involving alleged excessive use of force by deputies during the last two months are under internal review by the agency.

On the night of July 12th, 26-year-old Donavan LaBella was shot in the head by a deputy marshal with a non-lethal munition and suffered severe head injuries.

A week later, a U.S. Navy veteran, Chris David, said he was beaten with a baton and had a chemical irritant sprayed in his face when he tried to approach deputy marshals outside the courthouse.

Both incidents are reportedly also under investigation by the Department of Justice Inspector General Michael Horowitz, who announced he was launching a probe into use of force allegations by federal agents in Portland.

This week, Burger, Washington and other law enforcement officials met with community leaders to find solutions to the social unrest.

“One of the things that we’ve learned is that to resolve this, it can’t be a police response. It needs to be a community response,” Burger said.

Washington says the irony is that the Marshals Service has a long history of preserving civil rights in this country. When riots broke out following the enrollment of James Meredith, a Black veteran, at the University of Mississippi in 1962, teams of deputies protected Meredith 24 hours a day for the next year.

“The DNA of this agency is one of actually protecting civil rights, protecting this whole concept of civil justice as we go forward. And that’s what we intend to continue to do,” Washington said.

He said he agrees with the Chief Judge of the U.S. District Court in Portland who recently expressed his view that people should be yelling and shouting their grievances from the courthouse steps, not shouting at it, trying to burn it down and injuring officers.

With calls to pull federal law enforcement out of Portland, the Oregon State Police has taken over the security outside the courthouse. But inside, the marshals say they will maintain a long tradition of holding down the fort.

“With regards to our personnel inside, you know, we’ve been here as the director mentioned for 160 years, we’re not going anywhere.” Burger said. “The people that live and work here stay, and the additional deputies that are here to augment us. They’ll be leaving as soon as the violence stops, as soon as the attacks stop. And trust me, they’re ready to go home.”