The twitter says they were led away from the main group (likely by people who wanted them arrested) and onto the bridge, which was cordoned off beforehand, wher

The twitter says they were led away from the main group (likely by people who wanted them arrested) and onto the bridge, which was cordoned off beforehand, where they could be boxed in and justifiably (within the situation that the authorities created) arrested, but I don't really know because sadly, I wasn't there. My guess is that this is happening on Saturday because there's a hardcore group who stays in the square and on the weekends, when the numbers swell with working people who feel solidarity with the cause, they march.