This paper aims to address an important yet under-studied issue – how does violence from the side of the protestors affect overseas support for a democratic movement? The importance of this question is twofold. First, while violence and radicalization are not exactly unfamiliar territories for scholars of contentious politics, they do not receive as much attention when their effects spill beyond the domestic arenas. Second, this study seeks to examine international solidarity with democratic movements at the civil society level, which differs substantially from the conventional elite-centric approach when it comes to the intersection between democratization and international relations. Against this backdrop, this paper considers the relationship between violent tactics employed by the protestors during the anti-extradition movement and the sentiment expressed by people elsewhere towards the protests. To this end, a total of 9,659,770 tweets were extracted using Twitter Application Programming Interface during the period of 1 June 2019–31 January 2020. Leveraging computational methods such as topic modelling and sentiment analysis, findings in this paper demonstrate that a majority of foreign Twitter users were supportive of the protestors while held relatively negative sentiments against the government as well as the police. In addition, this study reveals that, broadly speaking, violence might cost a democratic movement by its international support, but could also garner more attention at times. Despite its restricted scope, this paper hopefully will shed some useful light on the dynamics underlying international solidarity for a democratic movement abroad as well as the complex mechanisms of interactions between people who protest at home and those who observe from overseas.