In this study, we will present an analysis of how polarization, and more specifically polarizing representations of immigrant communities, are discursively constructed in the online discourse of Belgian French-speaking politicians. Our study is based on Facebook and Twitter messages from leading politicians from all major parties. They consist of two one-month samples, which were collected one month before and during the 2019 electoral campaign for the regional, national and European elections that took place on May 26th. We will show how a variety of linguistic devices, such as deixis and metaphors (Lakoff and Johnson 1980), contribute to creating an opposition between an in-group and an out-group and to presenting the out-group as a threat, thus producing polarizing representations of immigrant communities.