BOSTON (WHDH) - Hundreds of climate change protesters blocked a bridge in Boston’s Seaport section on during rush hour Friday afternoon.

Activists, as part of an international grassroots movement called Extinction Rebellion, have flocked to the Congress Street Bridge to demand radical moves to fight climate change.

The event, known as Flood the Seaport, aims to grab state and federal politicians and advocate for policy that addresses climate change.

The bridge was completely impassable for more than three hours, video from Sky7 HD showed.

Police also gathered to help direct traffic around the peaceful protest.

The Bay State group joining hundreds of thousands of like-minded individuals from Italy, to New Zealand to Montreal, Canada.

Protestors say they are sorry for the disruption but say it is necessary to call for action.

“We’re here to stand up for the ocean. Stand up for the people to be impacted by sea-level rise and to say ‘Come on get on the ball, let’s do something,” Mike Fogelberg said.

Hundreds of thousands of young people skipped class last week across the world to take part in similar rallies.

Greta Thunberg, a 16-year-old Swedish activist marched Friday as well with Canadian Prime Minister Justin Trudeau.

“My message to all the politicians is the same,” she said. “To just listen to the science and act on the science.”

The latest report from the United Nations panel on climate change warns that the world may only have until 2030 to keep global warming below 1.5 degrees.

The panel, which is made up of more than 100 scientists from 36 different countries collaborate on the report.

Some amount of sea-level rise can no longer be stopped, according to scientists. But despite the damage done, humans can still have a choice.

Taking actions to end reliance on fossil fuels can ward off some of the worst projected impacts, according to the report.

This is a developing news story; stay with 7NEWS for updates online and on-air.

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