Abstract Social media has become an effective bidirectional communication tool used by risk management agencies during crises. Its interactive format can provide near real-time insight into public attitudes toward hazard and risk. While there is a growing body of research on risk communication and risk perception in developing countries, there is limited understanding of real-time public response to low-frequency, high-impact phenomenon like volcanic eruptions. Facebook, the social media platform, was one of the primary mass communication tools used by The University of the West Indies Seismic Research Centre during the 2020–21 eruption of La Soufrière volcano in St Vincent. This study analyses public response to hazard and risk information shared via Facebook. A thematic analysis of user comments and iconographic reactions during the eruption revealed a complex social response to the event and information on the event shared by scientists. Direct access to scientific information was widely appreciated, as was the scientific team, with whom the public developed a familiar relationship. The interplay of faith and science remains a key feature of risk perception in Caribbean society. Findings also highlight the utility of combining old and new broadcast technologies to engage diverse audiences.