About 90 people were arrested on Monday, according to the New York Police Department.

Founded less than a year ago, Extinction Rebellion , which has thousands of members around the world, has shut down swaths of London and other cities, recruited followers across Europe and beyond and pushed climate higher on the political agenda.

It stands out among environmental groups by disrupting “business as usual” with mass protests that mix doomsday mourning with sometimes-joyful street theater. The demonstrations demand governments “tell the truth” about the severity and immediacy of climate change, and ask them to reduce carbon emissions to net zero by 2025, years earlier than any official target.

Now, the group’s American members — at least 200 protested on Monday — are importing those tactics to a country where climate-change denial is more common .

Organizers and onlookers were unsure if the group’s tactics — demonstrators getting arrested, shutting down traffic — could work in the United States. But they agreed that with climate becoming more prominent on the political agenda here, it was worth a try.