Following the November 2003 attacks in Turkey by Turkish Islamist extremists, we designed an experiment to assess the religious identification of Turkish Muslim students using the inclusion/exclusion model of social judgment and social identity theory as general frameworks. Students (n = 193) were randomly assigned to experimental groups and then completed a questionnaire about religious identification. Groups varied in terms of the religious labels (i.e. Muslim vs specific religious sects) used for both the attackers and respondents in the introduction to the questionnaire. Results indicate that labeling terrorists as "Muslims" increased the respondents' religious identification when they focused on their identity as "Muslims", but decreased it when participants focused on their own sect membership. Regardless of the strength of their identification, being cast into similar categories with Islamist terrorists increased the ambivalence that Turkish citizens felt toward their religious identities. The highest ambivalent identification occurred when both respondents and attackers were categorized as Muslims. This research highlights the benefits and hazards of various identity management strategies that a Muslim society may employ in the face of Islamist terrorism. Future studies should address the changes in religious identification and ambivalent identification over time, and extend the current study to other populations.