Nearly 400 anti-Keystone protestors were arrested on Sunday after zip-tying themselves to a fence in front of the White House. Activist group 350.org characterized the action as the “largest youth civil disobedience at the White House in a generation.”

Those arrested were part of a larger student-led protest coordinated by XL Dissent. Organizers estimated that 1,200 people total participated in the march and rally that called on President Obama and Secretary of State John Kerry to reject plans to build the Keystone XL pipeline.

Here are some photos and tweets from the scene:

https://twitter.com/Solidus_Fahad/status/440348480104828929