NEW YORK — A day after 100,000 people marched to warn that climate change is destroying the Earth, more than a thousand activists gathered Monday in lower Manhattan’s financial district, chanting, carrying signs and – in some places – sitting down in the street to protest what they said was corporate and economic institutions’ role in the climate crisis.

There were reports of some isolated arrests of protesters, who police said did not obtain a permit for the rally. But by and large, the police, office workers and tourists watched alike as the activists chanted: “We can’t take this climate heat; we’ve got to shut down Wall Street,” and bounced two large, inflatable balloons meant to represent carbon dioxide bubbles. Police later punctured the balloons.

Ben Shapiro, an urban farmer and bread-maker from Youngstown, Ohio, said he didn’t participate in Sunday’s march but came specifically on Monday because he’s concerned about fracking, a technique that cracks open rock layers to free natural gas, and feels the financial system enables pollution.

“I wanted to come specifically to disrupt Wall Street because it’s Wall Street that’s fueling this,” Shapiro said while sitting next to the famed bull statute on Broadway. “I’m going after the source of the problem. … That means actively having to confront the system.”

The organizers of (hash)FloodWallStreet said the sit-in aimed to disrupt business in the financial district by targeting “corporate polluters and those profiting from the fossil fuel industry.”

The protest took a tense turn when demonstrators, after several hours of sitting and chanting near the bull statue, decided to march up Broadway and onto Wall Street itself. The protesters encountered barricades and a strong police presence outside the New York Stock Exchange. Some tried to push through the barricades, and tussles between demonstrators and police ensued. Police used pepper spray as they tried to hold the barricade.

Tourist Matilde Soligno, visiting from Bologna, Italy, came downtown to show a friend the famous bull and found it barricaded behind the demonstrators and the officers standing by. She took it in stride, snapping photos of the gathering.

“Every time I come here, there’s somebody here protesting,” she said. But, she added, “I think it’s a good thing.”

Demonstrator Nicholas Powers, who teaches black and feminist literature at SUNY Old Westbury, said that unlike Sunday’s protest, the sit-in was less about building consensus and more about confronting the institutions they feel are responsible for stalled political action to reverse global warming.

Dressed in a green wig and superhero outfit, protester Jenna DeBoisblanc said at a rally in a park near Wall Street before the protest that those assembled were expecting arrests at the sit-in.

“I think arrests in particular are a very good way of conveying the gravity of an issue,” said DeBoisblanc, an environmental activist from New Orleans. “If you’re willing to risk arrest it certainly demonstrates that it’s something very urgent.”