Earlier in the week, police spokesman Lieutenant Schwartz told the BBC they had been preparing for the summit for more than six months and had even held meetings with the main protest groups to coordinate their actions in advance.

BBC: A heavy police presence surrounded the talks

The Director of Tribal Affairs serves as the main point of contact between the Secretary and tribal leaders across the country, working with our intergovernmental partners to coordinate Department-level engagement with tribal elected officials, or their designees, related to key Department policy decisions.

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