SAN FRANCISCO (CBS SF) – Wearing ‘Water Is Life’ placards and chanting Native American prayers, hundreds of demonstrators including recording artist Michael Franti marched in San Francisco early Tuesday, shutting down a main city thoroughfare while protesting the construction of the controversial Dakota Access oil pipeline.

The march is part of a national day of protests including one in North Dakota where Robert F. Kennedy Jr. will join hundreds of demonstrators who have been camping and protesting near the construction site for months.

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Nearly 1,000 protesters began a three-prong march up three different streets in the San Francisco Civic Center area, causing rush hour traffic delays. They then proceeded down Market Street, shutting down traffic near the Civic Center on Market Street near 11th.

The protest was organized by groups including Diablo Rising Tide and Idle No More SF Bay and is part of a nationwide day of action against the pipeline, according to Idle No More organizer Isabella Zizi.

“We are not protesters, we are water protectors,” Zizi said.

Among the protesters was Carla, who took the day off to join in the protest.

“I’m just getting so tired of the government and big companies coming in and taking over people’s fresh water,” she told KPIX 5. “They are taking our money and leaving us poor and broken and disheartened. This makes me feel empowered… I’m part of the people who Bernie (Sanders) was talking about.”

Justin said he traveled from Arizona for the protest.

“I wanted to come out and give my support because the whole event is really a big deal for the Native American leadership,” he said.

Melissa, who was standing nearby, echoed the sentiments of most.

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“I work in coastal conservation so this hits pretty close to home,” he told KPIX 5.

Meanwhile, Franti — who lives in the Bay Area — put on an impromptu concert for the protesters.

The group began marching back to Civic Center Plaza shortly before 11 a.m. No arrests were reported.

San Francisco Municipal Railway officials said Muni routes that cross or operate on Market Street have been rerouted or turned around as a result of the demonstration, but by 12 p.m., traffic and bus service was back to normal.

On Monday, a large group of Dakota Access protesters caused the state Capitol in Bismarck to be locked down.

Meanwhile, Energy Transfer Partners — the company building the $3.8 billion Dakota Access oil pipeline – denounced a decision by the Army Corps of Engineers to delay an easement to cross a Missouri River reservoir in North Dakota.

CEO Kelcy Warren said in a statement Monday that the decision is “motivated purely by politics at the expense of a company that has done nothing but play by the rules.”

The Corps wants more studies and tribal input before it decides whether to allow the pipeline to cross under Lake Oahe. The 1,200-mile pipeline from North Dakota to Illinois is largely complete outside of the lake crossing.

The Standing Rock Sioux says the pipeline threatens drinking water and cultural sites. Protests have been ongoing in North Dakota for months with dozens of arrests including “Divergent” actress Shailene Woodley.

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