The viral dissemination of fake news threatens news organizations in Indonesia, with many social media users exhibiting a decrease in their trust of traditional media, as well as limited digital literacy. To investigate fake news during natural disasters, this mixed-methods study examines information patterns and journalistic practices of three news organizations during the 2018 Palu earthquake and tsunami. First, online observations of disaster-related fake news cases on social media provide insights into how fake news was handled by three types of news media. The results show that when fake news concerned factual scientific evidence, news organizations unanimously used the government statements to debunk disinformation. In contrast, political or religious fake news had long lifecycles of polarized debates between pro-government groups and opponents. Using the Hierarchy-of Influences Model, in-depth interviews showed that individual-level journalistic professionalism mattered when tackling fake news reports, with some local practices differing from Western journalism approaches. At the routine level, news professionals treated the government as the authority to debunk controversial, high-risk fake news by presenting news only after official clarifications, while independent media tended to present balanced reports with diverse views. Additionally, interviewees revealed that organizational policies in relation to media types greatly influenced the handling of fake news practices in Indonesian newsrooms. © 2020, © 2020 Informa UK Limited, trading as Taylor & Francis Group. Show More