Video footage from the student protest in the UQAM university in Montreal, Wednesday night, showed what appears to be a police officer pulling the hair of a protester. 
https://www.youtube.com/watch?v=NQPpe8pmNl8

Police baton-charge anti-racism protesters

Video footage from the student protest in the UQAM university in Montreal, Wednesday night, showed what appears to be a police officer pulling the hair of a protester.