Dozens of people in Pennsylvania's Lancaster County brought work towards a natural gas pipeline to a halt on Monday, charging that the project threatens a Native American cultural site and their rural way of life.

The protesters, who include area residents and a local chapter of the American Indian Movement, gathered along the Conestoga River and encircled a rig which was drilling for core samples at the site of a proposed pipeline, according to a statement from the group.

The drilling was for part of the Oklahoma-based Williams Partners' proposed $3 billion Atlantic Sunrise Project, a pipeline network that would pass through ten Pennsylvania counties, bringing gas from the Marcellus Shale to as far south as Georgia. It is slated to be in service in 2017.

The project has met strong opposition from area communities, and Lancaster County resident Carlos Whitewolf of the American Indian Movement vowed in November: "We will stand in front of your bulldozers. We will show up in big numbers, and you will have a war on your hands." But the pipeline opponents were dealt a defeat last month, when a Community Bill of Rights Ordinance that would have blocked the pipeline from Conestoga Township failed.

Monday's action, the protesters say, marks the first time they're using civil disobedience to disrupt Williams Partners' operations. But it might not be the last.

"Well over half of registered voters in Conestoga support an ordinance outright banning this pipeline," Leslie Bunting of Conestoga said in a media statement. "This action is an enforcement of the will of the people of Conestoga Township. The people of Conestoga Township are stopping this drilling today and any day in the future that Williams attempts it."

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