In this image made from video, a police officer uses pepper spray as he walks down a line of Occupy demonstrators sitting on the ground at the University of California, Davis on Friday, Nov. 18, 2011. Thomas K. Fowler/AP hide caption

itoggle caption Thomas K. Fowler/AP

University of California Davis Chancellor Linda P.B. Katehi walked through a three-block long group of silent protesters Friday night after campus police used pepper spray on some protesters earlier in the day. There have been calls for her resignation. http://www.youtube.com/lhfang86 hide caption

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