• A line of protesters against the construction of the Dakota Access oil pipeline on the Standing Rock Reservation in North Dakota head to a unity rally on the west steps of the State Capitol late Thursday, Sept. 8, 2016, in Denver. Several hundred marchers walked from the four directions to the Capitol to take part in the rally against the oil pipeline. (AP Photo/David Zalubowski)

    A line of protesters against the construction of the Dakota Access oil pipeline on the Standing Rock Reservation in North Dakota head to a unity rally on the west steps of the State Capitol late Thursday, Sept. 8, 2016, in Denver. Several hundred ... marchers walked from the four directions to the Capitol to take part in the rally against the oil pipeline. (AP Photo/David Zalubowski) (The Associated Press)

  • A protester holds up a placard against the construction of the Dakota Access oil pipeline on the Standing Rock Reservation in North Dakota head to a unity rally on the west steps of the State Capitol late Thursday, Sept. 8, 2016, in Denver. Several hundred marchers walked from the four directions to the Capitol to take part in the rally against the oil pipeline. (AP Photo/David Zalubowski)

    A protester holds up a placard against the construction of the Dakota Access oil pipeline on the Standing Rock Reservation in North Dakota head to a unity rally on the west steps of the State Capitol late Thursday, Sept. 8, 2016, in Denver. Several ... hundred marchers walked from the four directions to the Capitol to take part in the rally against the oil pipeline. (AP Photo/David Zalubowski) (The Associated Press)

Key ruling on Dakota Access Pipeline due by end of Friday

Markets Associated Press

A federal judge is set to deliver a key ruling on the four-state Dakota Access Pipeline that has drawn thousands of protesters to a construction site in North Dakota in recent weeks.

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U.S. District Judge James Boasberg says he'll rule by the end of Friday on the Standing Rock Sioux tribe's request to block the $3.8 billion project, which will carry oil from North Dakota to Illinois.

The tribe argues the project threatens water supplies and has already disrupted sacred sites. The developer, Dallas-based Energy Transfer Partners, says modern technology allows quick detection of leaks. Pipeline supporters also say it would cut the amount of oil that travels by train.

A weekend confrontation between protesters and private security guards left some guards injured and some protesters with dog bites.