Tens-of-thousands of demonstrators took to the streets of New York City Sunday to demand political leaders take action on climate change.

While the protest remained peaceful, much of the “People’s Climate March” appeared to be made up of fringe elements of the political left.

Image source: Oliver Darcy/TheBlaze

Image source: Oliver Darcy/TheBlaze

Dozens of signs denouncing capitalism were spotted at the demonstration, often held by self-proclaimed socialists.

“Capitalism is destroying the planet,” a sticker on one woman’s shirt read, “We need revolution, nothing less.”

Image source: Oliver Darcy/TheBlaze

Image source: Oliver Darcy/TheBlaze

In one instance, activists shouted “f**k the police,” demanding justice for the shooting of 18-year-old Michael Brown in Ferguson, Missouri.

Others took advantage of the demonstration’s liberal-leaning crowd, attempting to sell literature and t-shirts to them.

Image source: Oliver Darcy/TheBlaze

Image source: Oliver Darcy/TheBlaze

An individual with the socialist newspaper “The Militant” was selling newspapers to attendees, while Occupy Wall Street members asked for “donations” in exchange for shirts.

Image source: Oliver Darcy/TheBlaze

Image source: Oliver Darcy/TheBlaze

Image source: Oliver Darcy/TheBlaze

Image source: Oliver Darcy/TheBlaze

Members of the Socialists Workers Party also manned a table, passing out flyers attempting to make “the case for ecosocialism.”

The Manhattan march comes two days before the United Nations Climate Summit. More than 120 world leaders will convene Tuesday for the meeting aimed at galvanizing political will for a new global climate treaty by the end of 2015.

The march also coincides with New York’s annual climate week, which will include a string of events this week, some featuring celebrities, CEOs and climatologists.

The Associated Press contributed to this report.

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