As President Barack Obama and NATO leaders headed into Chicago this evening, demonstrators marched through the Loop for hours and sometimes scuffled with police officers. Several protesters were detained in the first serious confrontation of the day. Earliler, demonstrators spent the middle of the day outside Mayor Rahm Emanuel’s house protesting cuts in health care. Secretary of State Hillary Clinton arrived at Wrigley Field but did not sing "Take Me Out to the Ballgame."

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