evidence: Indonesia held its largest naval manoeuvres to date around the Natuna Islands, to which the PRC had made claims. [...] A PRC gunboat forced an Indonesian fisheries protection craft to release PRC vessels found fishing near the Natuna Islands. The waters around the Natuna Islands are internationally recognised as Indonesia’s EEZ. However, they also lie within the nine-dash line, and therefore are claimed by the PRC. [...] Chinese fishing vessels were escorted by the PRC Coast Guard into Indonesia’s EEZ in the North Natuna Sea. In response, Indonesia sent military patrols to the region. The PRC vessels eventually retreated, an action which may have been prompted by President Joko Widodo’s visit to the Natuna Regency. The PRC had previously recognised Indonesia’s sovereignty over the Natuna Islands.