At least 13 protesters were arrested Friday after they blocked the highway that leads to Mount Rushmore for hours with disabled vehicles.
The group positioned white vans across the road and took the tires off, making it more difficult to remove them.
Tow trucks eventually removed the vehicles.
Pepper spray was deployed during the clearing of the road.
Some of the group dispersed after South Dakota National Guard members arrived on the scene and officers declared the assembling unlawful. Others were arrested after declining to adhere to a 30-minute warning to leave the road.
The South Dakota National Guard referred The Epoch Times to Pennington County Sheriff's Department for information. The department couldn't be reached Saturday morning.
Protesters said they oppose President Donald Trump's administration. Trump, a Republican, was speaking during an Independence Day event at Mount Rushmore, a national monument.
"Respect our right to exist or expect our resistance. We are orphans crying in the night and we will keep making noise until they hear us," Freddie Longworth, a member of the Oglala Lakota tribe, told the Argus Leader. He said he was using the word orphans to reference Native Americans who were negatively impacted by treaties groups made with the United States.
A number of Trump supporters said they were unable to get through on the highway because of the protest group.