MANDAN, N.D. (AP) — Hundreds have gathered in front of the White House to protest the four-state Dakota Access pipeline as part of a wider “Day of Action.”

A cheerful, determined crowd gathered Tuesday afternoon in Washington to listen to speakers, including Sen. Bernie Sanders.

A couple of members from the Standing Rock Sioux tribe, which has filed a lawsuit against the pipeline and is leading a large protest near its reservation in North Dakota, were in attendance. One of them was a girl who joined about a dozen people from the reservation in running from North Dakota to Washington to deliver a 140,000-signature petition this summer.

Speakers called on President Barack Obama, who visited the reservation in 2014, to support their mission.

A federal judge declined Friday to block the pipeline, but the federal agencies stopped work near Lake Oahe while they re-examine their approval of the pipeline on Army Corps of Engineers’ land. They also asked the pipeline company to voluntarily stop work on a 40-mile (64 km) stretch, though it isn’t clear whether Energy Transfer Partners has complied.