“Divergent” actress Shailene Woodley joined about 30 Native American youth this weekend on their symbolic run to protest a new oil pipeline they consider a threat to their land.

The run started July 15 in North Dakota and will end Aug. 6 when the group—from the Oceti Sakowin, or Seven Council Fires, the proper name for the people commonly known as the Sioux—arrive in Washington, D.C. There, they will deliver a petition with more than 140,000 signatures demanding that the Army Corps of Engineers halt construction of the Dakota Access Pipeline.

The runners argue that the 1,172-mile-long pipeline will pollute their water and land. It will transport about 450,000 barrels of crude oil a day from the fracked Bakken Shale Formation of North Dakota all the way to Illinois. Construction has already begun in North Dakota, South Dakota, Iowa and Illinois.

During Woodley’s three-mile stretch, the 24-year-old actress and anti-fracking activist provided food, music, massages and new gear to the group. “The energy that she brought was just a big fire in a box,” says Christopher Walton, a runner and coordinator who is the partner of a Lakota woman who organized the run.

Woodley will rejoin the young activists in D.C. “We are here to stand together in solidarity with our Native brothers and sisters to say no to the Dakota Access Pipeline,” Woodley said in a Facebook live video posted to her page.

“We’re sacrificing our bodies to do this for humanity, for the people, for Unci Maka, Mother Earth,” said Bobbi Jean Three Legs, an organizer and Walton’s partner.

Screenshot courtesy of Shailene Woodley, taken from Facebook Live video on Aug. 1 Shailene Woodley, actress and activist, runs behind group of Native youth on their way to Washington, D.C., in protest of the Dakota Access Pipeline. Screenshot courtesy of Shailene Woodley, taken from Facebook Live video on Aug. 1, 2016

The group tries to have at least three people running on the road at all times. They log in at least 30 miles a day and 70 at most. They sometimes drive, especially in more urban areas or when law enforcement stops them.

Woodley can be seen running—and chanting—with them in a Facebook live video posted to her page. “We run for our people, for our nation,” she chants in one video. “We run for water. For life. We run for our brothers. For our sisters.” She also calls on Hillary Clinton to meet the runners in several Instagram and Twitter posts.

The Army Corps of Engineers finalized permits for the pipeline to cross tribal waters on July 26, to which the Standing Rock Sioux Tribe responded by filing a lawsuit against the corps for “violating the National Historic Preservation Act and other laws,” according to a statement sent to Colorlines.

The lawsuit states, “The construction and operation of the pipeline, as authorized by the Corps, threatens the Tribe’s environmental and economic well-being, and would damage and destroy sites of great historic, religious, and cultural significance to the Tribe.”

This run is part of the bigger Rezpect Our Water campaign, which launched in 2014 in opposition of the pipeline.