Thousands marched through lower Manhattan Tuesday night in solidarity with environmental activists and Native Americans hoping to stop the construction of the Dakota Access Pipeline on the Standing Rock reservation near Cannon Ball, North Dakota. As thousands more simultaneously protested in Philadelphia, Dover, San Francisco, Milwaukee, Bozeman, Ann Arbor, Bangor, Albuquerque, Eugene, Washington D.C., Los Angeles, Duluth, and Berlin, activists rallied outside the US Army Corps of Engineers office in TriBeCa as part of an international day of action demanding the Army put a stop to Energy Transfer Partners' plan to build an oil pipeline under Lake Oahe—a construction project that critics allege is both a threat to the clean water supply of local North Dakotans and an affront to the sanctity of Native land.

Photos and videos posted to social media throughout last night's protest documented the NYPD's efforts to stop demonstrators from taking to the streets and disrupting traffic. A police spokesperson confirmed 39 people were arrested during the Manhattan protest, with the vast majority charged with disorderly conduct.

Last night's protests were organized with the support of climate advocacy group 350.org and were timed to send messages of support to protesters gathered at Standing Rock, and pressure world leaders meeting in Morocco to discuss global climate regulations. Protesters also condemned President-elect Donald Trump's plan to slash environmental protections and expand the American coal and oil industries.

"The election of last week has made visible to the rest of the world the white supremacist forces of settler colonialism that Indigenous people and people of color have been fighting all along," Crystal Migwans of the Anishinaabe Nation said Tuesday. "It is now more important than ever to stand with the water protectors at Standing Rock; to turn our attention to the heart of the continent rather than turning away in resignation. The struggles for land, water, and lives there, at what seemed like a distant corner of the world before, should be forefront in all our minds now."

On Monday, the Army Corps of Engineers published a letter claiming that pipeline construction must remain in limbo. The Corps promised to cooperate with North Dakota's Sioux allowing for "robust discussion and analysis to be completed expeditiously."

Protesters carrying banners and signs chanted their demands for a stop to the pipeline project beginning at 4 p.m. Tuesday. At about 6:30 p.m., demonstrators moved into the road to block traffic and began getting arrested by police.

Brooklyn resident and climate change activist Michael Dobson told us, "The legacy of this country's treatment of its indigenous peoples is something every American should care about and be willing to confront. What is happening all around this country today is that people are taking responsibility for the actions of their government. They are standing in solidarity with the people of Standing Rock, because they recognize that their struggle—for clean water and a livable environment—is our struggle."

Nicole Goodwin, an Iraq war veteran, addressed the rally Tuesday. “Today, Iraq Veterans Against the War stood in solidarity with Standing Rock and delivered a letter that our members wrote to the Army Corps of Engineers telling them to stand down," Goodwin said. "It is especially important for veterans and service members to stand with Standing Rock because we have the responsibility to rectify the US military's history of occupation. We went to the Army Corps today to tell them to deny permits for DAPL, to tell them that we are watching their moves, and that the core values of this country are in danger unless they act."

Throughout the 2016 general election, many opposed to the Standing Rock pipeline became frustrated with both major party candidates. Democratic nominee Hillary Clinton's tepid call for more discussion drew harsh criticism from activists, while President-elect Donald Trump never so much as acknowledged the protests during his campaign. Vermont Senator Bernie Sanders, however, made repeated calls for a stop to construction. Sanders made an unannounced visit to #NODAPL protests last night in Washington, where he called on President Obama to declare Standing Rock reservation a national monument.

"Make no mistake," Dobson said. "The next four years will be a struggle. The election of Donald Trump should be deeply concerning for anyone who cares about the environment. America elected this man and now America is responsible for him. If that means we have to be in the streets every day of the next four years to insist that a Trump administration doesn't turn America into another Saudi Arabia, and doesn't abandon vulnerable people here and around the world to the destruction of climate change, then so be it. It starts today."