In Santiago, Chile, thousands attend a protest called the "Fridays For Future" movement.
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In Bangkok, students show placards during a demonstration to protest against climate change.
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In Berlin, the youths show their hands with the inscriptions "Our future in your hands" during the protests.
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In Italy, students hold posters during a protest in central Turin.
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In Austria, a youth cries a slogan during a climate protest outside the Hofburg Palace in Vienna.
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A youth movement that started with a teenager in Sweden was spread all over the world on Friday, shown by students from London to New Delhi, who skipped school to attend demonstrations requiring action on climate change.
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The sixth year old Greta Thunberg completed the movement last summer in Sweden and received attention when she handed in a strong speech at the UN's climate summit in December.
This wave of demonstrations so far one of the biggest turnouts, including protesters in almost all states in the United States, attends an event organizer called "US Youth Climate Strike. " Strikes and demonstrations were planned in more than 100 countries and territories, including South Africa, India, New Zealand and South Korea. In Europe, students in Lisbon, Vienna, Rome and Copenhagen marched among other cities.
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Bay Area students marched down Market Street in San Francisco, first gathered at Democratic Rep. Nancy Pelosi's office, San Francisco Chronicle reports. Like other students across the country, the group urged lawmakers to act. They had handmade characters demanding a Green New Deal, the ambitious framework for future legislation designed to accelerate the country's transition to carbon-free energy and revise the US economy to spread wealth more evenly.
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Students in Hong Kong bore signs reading "There is no planet B" and "You destroy our future" as they joined the worldwide protests. The organizers of March have asked the government to set up youth representatives in its governance committee on climate change, according to Hong Kong Free Press.
New York City
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In Manhattan, 16 protesters were arrested for blocking traffic during a "die-in" in front of New York's Natural History Museum, reports AP.
Protests took place throughout the city as students marched through Central Park and packed into Columbus Circle. A protest brought a sign to read: "I do not discover school because adults do not appear to be climate." Washington Gov. Jay Inslee, candidate for the democratic presidential election, spoke to a crowd from the steps of Columbia University's library. Inslee has said addressing the climate is at the heart of his campaign.
St. Paul, Minn.
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In the Twin Cities, students at the state's Capitol met to protest against inaction against climate change. "We have to cause rebellion," Maya Sprenger-Otto, an organizer and student, told a crowd on the Capitol rods, Minneapolis Star Tribune reports. "We will not be stopped until significant change occurs."
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Students in cities throughout Portugal participated in the protests, including in the country's capital, which responded to social media calls. They filled the streets with signs of reading "Water and oil do not mix" and "Titanic would survive in 2049."
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Thunberg, who inspired the "school attacks", spoke to a crowd in Stockholm on Friday. The teenager was nominated for the Nobel Peace Prize this week.
"We are facing an existential crisis, the greatest humanity ever facing," said Thunberg, according to the Swedish public television station SVT. "We will live with this crisis throughout our lives. We will not accept it."