MANDAN, N.D. — As authorities in North Dakota braced for the arrival of more than 2,000 veterans joining the protests against the Dakota Access pipeline this weekend, local law enforcement officials on Saturday criticized the Obama administration for not doing more to resolve the ongoing standoff over the project.

Attorney General Loretta E. Lynch announced Friday in a videotaped statement that she was dispatching federal mediators to ensure the ongoing standoff between protesters and police over the pipeline did not erupt into violence.

Lynch, who made calls Friday to both Morton County Sheriff Kyle Kirchmeier and the Standing Rock Sioux Tribal Chairman David Archambault II, said that she had offered community policing resources to local officials and had sent “conciliators from the Community Relations Service to North Dakota.”

Kirchmeier and Cass County Sheriff Paul Laney said that while they had spoken with Lynch, administration officials needed to intervene more directly to avert possible violence. In a news conference Saturday afternoon, a visibly frustrated Laney blasted the decision only to send mediators, saying the administration had ignored repeated requests to engage with tribal leaders.

“We’ve asked numerous times, come help. It’s a federal reservation, and they are camped on federal land. How can you tell me it’s not a federal problem that’s been dumped into local laps?” Laney said, speaking at city hall in Mandan.

Officials said they have received “very concerning” reports that a small minority of agitators in the otherwise peaceful camp near the Missouri River may try to incite violence against authorities during planned demonstrations Sunday and Monday. Protest organizers say they have no intention of confronting police and have pledged to remove anyone who acts aggressively.

Laney said the protest movement has “made its point” and called on President Obama and his aides to step in and resolve the dispute over the pipeline in federal court.

“What have we seen? Nothing,” Laney said. “Some token, ‘Oh, we’ll send you a couple people on the ground to come and talk.’ How about you send a representative from the Obama administration to engage with the tribe and start alleviating their concerns, start discussing what’s been happening, and start de-escalating these threats?”

Kirchmeier echoed his concerns, saying meetings with mediators have yielded little progress.

“This issue is not going to get solved out on the roadway or on the prairie with law enforcement and protesters standing and looking at each other,” he said.

Laney said officials expected the demonstrations to remain calm. But he said police had received “very concerning intel” that a small group of agitators “wants to exploit veterans with PTSD, arm them and try to trigger their PTSD and turn them aggressive.”

“Besides being horrible and wrong,” he said, “it could be dangerous and deadly.”

Laney and Kirchmeier, who were joined by Maj. Gen. Alan Dohrmann of the North Dakota National Guard, said authorities would pull back from a bridge near the camp as early as 4 p.m. Sunday to make way for the veterans’ demonstrations. The bridge is barricaded with burned-out cars, concrete barriers and razor wire, and has been the site of recent clashes with law enforcement. As long as protesters remain south of the bridge and do not try to remove the barriers, authorities will pull back “to an area that gives us separation from law enforcement and the protest groups,” Laney said.

Tensions between law enforcement and activists have escalated at the main protest site, Oceti Sakowin Camp, which Army Corps of Engineers officials have ordered evacuated by Monday. North Dakota Gov. Jack Dalrymple (R) also ordered those encamped at the site to leave in the wake of a snowstorm earlier this week. Hundreds of veterans have arrived and vowed to shield the protesters from being forcibly removed.

“Let me stress that violence is never the answer and that all of us have a responsibility to find common ground around a peaceful resolution where all voices are heard,” Lynch said in the video. “Our first concern is the safety of everyone in the area — law enforcement officers, residents and protesters alike.”

Given the administration's general reluctance to insert itself in the ongoing controversy surrounding the $3.7 billion pipeline, Lynch's decision to send agency representatives to the site was notable. While federal officials have convened meetings with tribal representatives to address their concerns over the route, which they argue could threaten their water supplies as well as sacred sites, Obama has commented only sparingly on the project.

After White House press secretary Josh Earnest was asked Monday whether the president would intervene given the pending federal evacuation order, he replied, “At this point, I'm not aware of any impending presidential actions” regarding the project.

At the Oceti Sakowin Camp, Lynch’s remarks were met with a shrug. Several activists said that they were glad the Obama administration had weighed in on the ongoing standoff with law enforcement, but they expressed skepticism that the federal mediators would contain what they view as an overly militarized police presence.

William Good Bird, a Standing Rock native, read Lynch’s statement on an iPhone while sipping a cup of coffee near a prayer fire at the center of camp.

“They say they’re going to deploy? Well, I’m still going to be here. I live here,” Good Bird, 32, said. “Why don’t they sit down and talk with us?”

On the hilltops about a half-mile from the northern edge of the camp, more than a dozen spotlights erected by police shine down on the snow-covered fields below to deter people from advancing toward the pipeline’s construction sites. Armored police vehicles patrol the hills daily, and helicopters periodically circle the camp. A bridge several hundred feet up the road is barricaded with concrete barriers and razor wire, and police stand guard on the opposite side.

Tribal leaders have urged activists to remain “peaceful and prayerful” and have even kicked out some protesters caught throwing rocks and bottles at police, organizers say.

Despite promises from the Army Corps and the governor’s office that authorities will not forcibly clear the camp once Monday’s evacuation deadline passes, many activists said recent clashes between protesters and law enforcement have left them worried. The Morton County Sheriff’s Department has arrested hundreds of protesters so far, and many activists have criticized the police for employing tactics such as water cannons, pepper spray and rubber bullets.

“Last month, it felt like a war zone. When you deploy all these militarized police, I have to wonder, will we go through Wounded Knee again?” said Good Bird, referring to the 1890 massacre of more than 150 Lakota by U.S. Army troops in South Dakota.

Camp organizer Dallas Goldtooth tweeted out Lynch’s video, calling it a “good sign that we have the [administration’s] attention.” Her statement, he said, “is frustrating but demonstrates that they are being pushed to respond.”

Virginia Red Star, a 40-year-old member of the Colville tribe visiting the camp from Washington, was listening to a group of five Sioux men beating drums and singing songs under a small wooden enclosure late Friday night. She said that she was not interested in actions from the White House unless they “lifted our prayers.”

“I’d like the administration to tell them not to build the pipeline in the river, that’s all,” Red Star said. “I’d like them to grant that to our people.”

Lynch said that her department has “made strenuous efforts to open lines of communication and dialogue between law enforcement, tribal leaders and protesters,” including by engaging the Office of Community Oriented Policing Services (COPS).

“We recognize the strong feelings that exist about the Dakota Access Pipeline — feelings that in many instances arise from the complicated and painful history between the federal government and American Indians,” she said. “We will remain committed to working with all stakeholders to enforce the law; to maintain the peace; and to reach a just solution to this challenging situation.”

While Obama has raised the possibility that the project could be rerouted, President-elect Donald Trump has suggested it should proceed as planned. As recently as May, Trump owned stock in the firm constructing the pipeline, Energy Transfer Partners, as well as one of its major investors, Phillips 66, according to financial disclosure forms.

One of Trump’s aides, Bryan Lanza, wrote in a memo that was obtained Friday by the Associated Press that the businessman’s support for the project “has nothing to do with his personal investments and everything to do with promoting policies that benefit all Americans.”

The president-elect met Friday in New York with Sen. Heidi Heitkamp (D-N.D.), who backs the pipeline.

Eilperin reported from Washington.