The internationalisation of higher education has been challenged by the significant decline in international student mobility caused by the COVID-19 pandemic. The emergence of internationalisation at a distance before COVID-19 paved a new avenue for the internationalisation of higher education, with the distinctive feature of knowledge mobility without human mobility. However, few studies have explored knowledge mobility in an internationalisation at a distance context. The ethnographic case study identifies three knowledge mobility channels -- Information and Communication Technology (ICT), curriculum and virtual community of practice -- and argues that the knowledge creation model SECI (Socialisation, Externalisation, Combination, and Internalisation) is inapplicable in the internationalisation at a distance context. Additionally, the absence of immersion in face-to-face interaction hinders internationalisation at a distance students' identity construction, placing them at a disadvantage in acquiring tacit knowledge. The significance of cultural, linguistic and pedagogical contextualisation in the context is also emphasised.