The Ministry of Health in Singapore was alerted to two individuals with locally acquired COVID-19 on Feb 3, 2020 (AC1 and AC2; figure 1 upper panels). They did not fit the case-definition for suspected COVID-19 but were tested because they reported frequent occupational contact with Chinese tourists. These two people were later identified to be linked epidemiologically to two other affected individuals (AGX1 and AGX2), a father and daughter reported by official and media websites in Guangxi, China,8, 9, 10 to be Chinese tourists who travelled to Singapore on Jan 22, 2020, and who visited several tourist sites on Jan 22–23, 2020, as part of a tour group. AGX1 and AGX2 subsequently departed for Malaysia before re-entry into Singapore for their flight to Guangxi on Jan 27, 2020, and they developed symptoms on Jan 28, 2020, after arrival in Guangxi. Details of the tour participants and the itinerary, obtained through the Singapore-based tour guide for the Singapore tour segment (AT1, who also tested positive for SARS-CoV-2) corroborated with details for AGX1 and AGX2 reported by Guangxi websites.