Before presumptive House Speaker Nancy Pelosi (D-Calif.) even appeared at her office to hear from young Americans who had traveled from all over the country to urge her to back a Green New Deal, Capitol police arrived Monday and arrested more than 60 of the protesters. As of this writing, at least 143 demonstrators had been arrested as they lobbied in 50 congressional offices.

More than 1,000 young people and allies flooded the Capitol Hill hallways and offices of Democratic representatives to demand that elected officials listen to their youngest constituents—as well as some of the world's top scientists—and back the bold proposal to shift the U.S. to a zero-carbon energy system by 2050 in order to save the planet from an irreversible climate catastrophe. Thanks to efforts spearheaded by the youth-led Sunrise Movement, the number of Democratic lawmakers now supporting a Select Committee on a Green New deal has now swelled to 23.

"When the people rise up, the powers come back. They tried to stop us but we keep coming back," sang the protesters as they occupied Pelosi's office.

Protesters at @NancyPelosi’s office demanding Democrats address climate change and a green new deal as part of taking the Majority next year - an effort @ocasio2018 pushing for. pic.twitter.com/M2ZajA9D2Q — Alex Moe (@AlexNBCNews) December 10, 2018

The joys of our songs clash with the heavy thunk of zip ties tightening against th wrists of young people. Arrests happening now at @TeamPelosi’s office, but no sign of @NancyPelosi. Add your name for a #GreenNewDeal https://t.co/GH2GSW1QEl pic.twitter.com/nbLwqmvJKy — Sunrise Movement (@sunrisemvmt) December 10, 2018

Supporters of the Sunrise Movement posted images and a time-lapse video of the huge group that lined the halls.

Today, on #HumanRightsDay, we join 1000 young people from across the country w/ @sunrisemvmt to hold our leaders accountable. #NoExcuses to #ActOnClimate, esp. when we can create millions of jobs in the process. We need a #GreenNewDeal! pic.twitter.com/X0UP1JA1OZ — Hip Hop Caucus (@HipHopCaucus) December 10, 2018

Wayyyyyy down at the end of the hallway is @NancyPelosi's office.@sunrisemvmt is OVERFLOWING her office and winding allllll through the halls for a #GreenNewDeal pic.twitter.com/e24TBvnW1V — Will Lawrence (@wlawren90) December 10, 2018

The protesters, 800 of whom had attended a training on lobbying members of Congress and their staffers the previous evening, carried signs reading, "Do Your Job," "Back the Deal," and "No More Excuses"—winning praise from high-profile climate action campaigners including 350.org founder Bill McKibben.

"These young people will spend the next seven decades living in an overheated world—they have the moral high ground," wrote McKibben on Twitter, posting a photo of the protesters.

More than a thousand demonstrators from the @sunrisemvmt are now sitting in at the offices of the Dem congressional leadership demanding action on a #GreenNewDeal. These young people will spend the next seven decades living in an overheated world--they have the moral high ground. pic.twitter.com/JN2EGgte6T — Bill McKibben (@billmckibben) December 10, 2018

Many also wore T-shirts emblazoned with the following message: "We have a right to good jobs and a livable future," two key components of the Green New Deal, which would create 10 million jobs in the first decade by putting Americans to work building a green energy infrastructure that would be sustainable for decades and centuries to come—unlike the current coal-, oil-, and gas-reliant system which scientists say will push the warming of the planet past the point of return unless carbon emissions hit net-zero by 2050.

The halls erupted in cheers when Rep. Jim McGovern (D-Mass.), the incoming chair of the House Rules Committee, told the group that he would join 22 of his colleagues in backing the creation of a House Select Committee with a mandate to pass a Green New Deal.

Wow. A few hundred of us are at incoming House Rules Committee chair @RepMcGovern's office. He just told us: "I am committed to a Select Committee on a #GreenNewDeal." SCROLL TO CONTINUE WITH CONTENT Never Miss a Beat. Get our best delivered to your inbox.





Thank you for your leadership, Rep McGovern. We're going to win. pic.twitter.com/DGOHL41Acb — Sunrise Movement (@sunrisemvmt) December 10, 2018

Lots of joy and applause as incoming Rules Committee chair affirms his support for a Select Committee on a #GreenNewDeal and the bold climate action we need.@NancyPelosi, @WhipHoyer: you're next. Will you stand with us? There are #NoExcuses for anything less. pic.twitter.com/kVlQHTTuEf — Sunrise Movement (@sunrisemvmt) December 10, 2018

One of the youngest participants in the action visited McGovern's office to tell him, "I'm here to protect vulnerable communities." At least one nine-year-old also attended the action.

Odin is the youngest visitor to @RepMcGovern's office today. "I'm here to protect vulnerable communities." Rep. McGovern, we believe you'll stand with Odin & on the right side of history and help make the Select Committee for a #GreenNewDeal a reality. Can we count on you? pic.twitter.com/sVvHU7HILM — Sunrise Movement (@sunrisemvmt) December 10, 2018

Her name is Tahlia and she is fighting for her future and yours! In 12 years, she will be 21, and what will the world look like? It’s up to you! #greennewdeal #nomoreexcuses #sunrisemvmt ⁦@sunrisemvmt⁩ pic.twitter.com/et2OUqsZwB — Liz Elkin (@lizzyelkin) December 10, 2018

Dozens of protesters were also arrested at the office of House Minority Whip Steny Hoyer (D-Md.), who despite promising that the new Democratic House majority will "act on climate," said only that "Speaking out is exactly what our democracy is all about, and I appreciate [protesters'] passion" in a tweet on Monday.

HOYERS: Arrests are starting as Capitol Police arrive. There are dozens now sitting in outside @WhipHoyer office until he commits to support select committee on #GreenNewDeal pic.twitter.com/IkgYfgsK6a — Sunrise Movement (@sunrisemvmt) December 10, 2018

After the office visits, progressive Senate candidate Kerri Harris of Delaware joined the Sunrise Movement in rallying hundreds of demonstrators outside the Capitol at a gathering where young participants shared their own stories about what drove them to protest.

.@KerriHarrisDE closes out our rally with a message of hope. “You all are showing @HouseDemocrats how to lead!” #GreenNewDeal pic.twitter.com/5RiiBY2DTI — Sunrise Movement (@sunrisemvmt) December 10, 2018