North Dakota regulators say the Keystone pipeline leaked more than 383,000 gallons of oil in the northeastern part of the state.
The $3.8 billion Dakota Access pipeline began shipping oil for customers on Thursday, as Native American tribes that opposed the project vowed to continue fighting.
Authorities in South Dakota on Tuesday confirmed an incident of vandalism against the Dakota Access oil pipeline in which someone burned a hole through an empty section of pipe.
A federal judge has declined to temporarily stop construction of the final section of the Dakota Access pipeline. It means the pipeline could be operating this month.
With the green light from the federal government, the company building the Dakota Access oil pipeline said Wednesday it plans to resume work immediately to finish the long-stalled project.
The Army said Tuesday that it will allow the $3.8 billion Dakota Access oil pipeline to cross under a Missouri River reservoir in North Dakota, clearing the way for completion of the disputed four-state project.
President Donald Trump has signed executive actions to advance the construction of the Keystone XL and Dakota Access oil pipelines.
President-elect Donald Trump supports completion of the disputed Dakota Access oil pipeline in the Midwest, a policy that a spokesman says is not related to Trump's investments in a partnership building the $3.8 billion pipeline.
Hundreds of clergy of various faiths joined protests Thursday against the Dakota Access oil pipeline in southern North Dakota, singing hymns, marching and ceremonially burning a copy of a 600-year-old document.
President Obama says the U.S. Army Corps of Engineers is examining whether the Dakota Access oil pipeline can be rerouted in southern North Dakota to alleviate the concerns of American Indians.