Rep. Kevin Cramer (R-ND) said on "Happening Now" today that the Standing Rock Sioux tribe's peaceful protests over the Dakota Access oil pipeline were "co-opted" by groups with a separate agenda.

On Sunday, the U.S. Army Corps of Engineers’ denied a permit for the North Dakota pipeline after the Native American tribe argued that the construction would threaten its water source and damage its sacred grounds.

Thousands, including veterans, joined the tribe on federal land to protest the pipeline going through Lake Oahe, a Missouri River reservoir.

Cramer, who was set to meet today with President-elect Donald Trump on the issue, criticized the Obama administration for meddling in the decision for political reasons. 

He said the tribe has expressed "legitimate concerns," but their movement was then used by left-wing activists whose agenda is "keeping oil in the ground."

"They've been co-opted by a very different element and consequently, the tragedy is their legitimate questions have been deluded by this other argument that's come into play," he said.

Earlier in the show Billy Mills, a member of the Oglala Lakota tribe and a 1964 U.S. Olympic gold medalist, discussed his support for the protesters with Jenna Lee.

Watch the clips above and below and read more on the story, here.

USS Arizona Survivor to Visit Pearl Harbor Memorial on 75th Anniversary of Attack

Mike Rowe to Fan: The American Flag is More than a 'Mere Symbol'

Woman Proudly Wears Her $130 Wedding Ring: 'It Isn't the Ring That Matters'