This article examines how crises catalyse intergroup threat expression, focusing on the European refugee crisis and the Covid-19 pandemic. We analysed Estonian-language Facebook posts, which had the maximum number of user engagements per quarter, and the content linked within these posts on the topic of forced migration from 2014 to 2020. Applying the discourse-historical approach, we analysed threats attributed to forced migrants. The results reveal that the refugee crisis opened a discursive window of opportunity for expressing existential, economic, and religious threats, and the pandemic for health threats. Realistic threats proved to be more persistent, with symbolic threats amplifying the threat perception when combined. Since the refugee crisis, radical right actors used the combination of different threat types to mobilise electoral support, and during the pandemic, a pro-Russian (dis)information network employed a similar strategy to spread divisive content. The study advances intergroup threat theory by showing how threat types interact and by proposing a temporal framework for understanding how threat discourses are strategically used on social media.