In this study, predictors of post-traumatic stress symptom levels (PTSSL) and post-traumatic growth levels (PTGL) resulting from the experience of violence were investigated. The sample of the study consisted of 514 Gezi Park demonstrators. Participants completed measures assessing stress symptoms, post-traumatic growth, social support and beliefs about the world as well as the open-ended event specific questions. Results showed that being politically active, psychologically prepared and experiencing mild levels of violence were related with decreased PTSSL individually but not in combination as the literature suggested. The two hierarchical regression analyses showed that: (1) PTSSL were predicted by violence exposure levels, perceived social support from significant others and "randomness" and "self-worth" beliefs about the world; (2) PTGL were predicted by violence exposure levels, total amount of time spent at the demonstrations and "benevolence" and "justice" beliefs about the world. These findings suggest that psychological preparedness might be an important variable in violence experience regarding human masses. Also, violence exposure levels and duration of participation seems to be important event- specific variables. Lastly, political activism needs to be more precisely operationalized and measured in future studies.