Demonstrators gather on Capitol Hill in Washington on Saturday to protest the Dakota Access oil pipeline. (Alex Brandon/AP)

Hundreds of protesters gathered Saturday on a cold and blustery Mall to show support for the Standing Rock Sioux Tribe in its effort to halt work on a pipeline in North Dakota that the tribe says threatens its water supply and destroys sacred ground.

The Dakota Access Pipeline, or DAPL, has been the focus of a year-long battle between the petroleum industry and a growing coalition of Native American tribes and environmentalists. The protesters have created a camp in North Dakota adjacent to the Standing Rock reservation and a mile from where the pipeline is planned to cross the Missouri River.

With the U.S. Capitol in the background and the National Museum of the American Indian a half-block away, Saturday afternoon’s “Standing Rock & Beyond #NoDAPL” protest began with the sound of drums and chanting filling the chilly air as members of the Rosebud Sioux Tribe of South Dakota pounded out a rhythm and cried out in prayer.

“When I have kids, I want them to know what clean water tastes like. I want them to know what it feels like to swim in that water,” said Emerson Little Elk, 20, who led the singers. “That’s why we have to be out here so that people everywhere will know what’s going on at Standing Rock. Little Elk and the other drummers arrived Friday night from the Standing Rock camp, where they have lived for the past four months.

Juanita Cabrera Lopez, of the Maya Mam Nation, says a prayer on Capitol Hill on Saturday during a demonstration to protest the Dakota Access oil pipeline. (Alex Brandon/AP)

The tribes and their supporters tasted victory on Dec. 4, when the Army Corps of Engineers denied a permit for the section of the pipeline that would go under the Missouri. But many observers believe that victory will be short-lived as president-elect Trump has indicated he supports completion of the pipeline.

The crowd booed loudly when Jordan Daniel, a member of the Lower Brule Sioux Tribe who lives in Washington, reminded them that Trump would likely approve the pipeline. She urged them to be vigilant and continue fighting to make their voices heard.

“Don’t let them forget you,” she said. “Keep spreading the word.”

In the crowd, flags waved and signs were held high: “Water is Life!,” “Veterans Stand with Standing Rock,” “Stop Letting Corporations Poison our Water,” and “When did We the People become We the Corporations?”

While most in the crowd were from the Washington region, others came from as far as Arizona, New Mexico and California. Genaro Cilel, 47, a Mayan Indian originally from Guatemala who now lives in Philadelphia, stood with his three young daughters watching the protest from the edge of the Capitol Reflecting Pool. Cilel said it was important for him to be there to show solidarity with other tribes.

“As Mayans, we take care of water,” he said. “It is sacred to us. It gives us life.”

Ashley Holst, 26, who recently completed a master's degree at American University, also came to the event to show support for the Standing Rock tribe and to protest what she described as environmental inequities.

The tribe “didn’t want this pipeline, but because of their racial and economic background they were being forced to accept it,” Holst said. “The issues around water are really important and they keep popping up. People need to pay more attention to these issues.”

Following the rally on the mall, the protesters marched to the office of the Environmental Protection Agency on Pennsylvania Avenue to register opposition to the incoming administration, said Sebastian Medina-Tayac, 21, a member of the Piscataway Indian Nation and one of the lead organizers of the march.

“This is a really powerful moment in history,” said Medina-Tayac. “It’s a long legacy of Native resistance. This is us asking for basic human rights and dignity and were fighting for our very survival.”