The federal government ordered a halt to work on a $3.8 billion four-state oil pipeline in the Upper Midwest on Friday, handing a temporary victory to the Standing Rock Sioux tribe and other opponents of the project.

The unusual move by three federal agencies immediately followed a federal judge’s ruling denying an injunction sought by the tribe. The judge said the Dakota Access Pipeline would be able to proceed.

Brigham McCown, who once led the federal Pipeline and Hazardous Materials Safety Administration, said the federal agencies’ move looked like political capitulation to pressure from activists, who have homed in on energy infrastructure as a way to challenge fossil fuel development.

“To me this clearly looks to be political involvement in a process that has already played out through the courts,” he said. “These projects are certainly much more at the forefront of activists than they have been in the past.”

Read more in the Wall Street Journal.