CHICAGO (CBS) — Following an anti-NATO march to McCormick Place and conflict with police, protesters staged a late night sit-in front of the Art Institute where Michelle Obama was hosting a dinner.

A group of several hundred people, trying to send a message to the first ladies of all the NATO nations attending the event inside, were sitting in the middle of Michigan Avenue in a driving rain.

The protesters chanted “Our Streets, Our Streets” as a large line of Chicago police officers in riot helmets lined the Art Institute’s entrance.

The group started dancing as the rain fell, in a stark contrast to the end for the larger protest march earlier in the day.

VIEW: Scenes From The Protest March

By late Sunday, the group was on the move, winding through Chicago’s downtown and monitored by police.

nato art institute1 Protesters Stage Michigan Avenue Sit In In Front Of Art Institute

Protesters gather outside the Art Institute on Sunday night. (Credit: Mason Johnson/CBS Chicago)

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