Dorchester’s Danny Luker, 66, will return to the Standing Rock Indian Reservation in North Dakota this week to continue his support for that community as it fights to prevent a controversial oil pipeline under the Missouri River.

This will be the second visit to Standing Rock for Luker, a Vietnam veteran who joined more than 4,500 armed services veterans there in December. They were among 15,000 people who came out to protest the lack of an environmental impact statement detailing the effects of what is called the Dakota Access Pipeline.

“I saw the videos of the police firing the water cannon on the protestors, and that was it for me,” said Luker, who lives in the Ashmont neighborhood with his wife, Emmy Rainwalker. “I knew that wasn’t right, to hit people on their own land like that, in subfreezing weather.” Luker was referring to footage that circulated on social media and news outlets of protestors being met with water cannons, pepper spray, and tear gas as they attempted to force their way through barricades set up by police.

Members of the Standing Rock Sioux Tribe and other Native American allies have been leading efforts to halt the project. They won a victory in the waning days of the Obama presidency, when the outgoing administration issued a stop-work order. But the Trump administration has directed its immediate resumption.

The Dakota Access Pipeline is meant to carry crude oil from the Bakken oil field in North Dakota through the Dakotas and Iowa to Illinois. Protestors worry that the line will be laid in sacred Indian burial grounds, and also that it will pose a threat to the drinking water supplied by the Missouri River.

Luker says he feels a sense of catharsis participating in the protests. “It was healing to be on the right side of a war for a change,” he said.

Luker said that when he joined the military, he took an oath to defend the country from all enemies, foreign and domestic. At least 4,000 veterans, he said, share his belief that they working to still defend the country.

For the next two weeks, Luker will be looking to help in Standing Rock in whatever capacity he is needed. “For clean up, or for security, I’ll do anything” Luker said. “The Native Americans are just amazing.”

Members of the group Dorchester People for Peace are planning a meeting for Thurs., Feb. 16, in St. Mark’s School Hall to get updates on the resistance effort. Ms. Rainwalker will be among the guest speakers at the event, which will start at 6:30 p.m.