The United States Army Corps of Engineers has denied a permit that would be needed to complete a major oil pipeline under the Missouri River. The announcement on Sunday ended a tense situation between the U.S. government and several thousand people. They had set up a protest camp on federal land in North Dakota. For months, the Standing Rock Sioux tribe has been leading demonstrations against the Dakota Access Pipeline project. The tribe says the pipeline would affect its drinking water supply and destroy its holy places. The Corps of Engineers is responsible for studying and approving permits for all water crossings nationwide. In North Dakota, protesters are celebrating the federal agency’s decision. Many people who followed the story on social media also are celebrating. They posted articles and videos about the news on social media sites, such as Facebook and Twitter.