A foreign tourist on a package tour trial in Oita Prefecture has tested positive for the coronavirus, with three others considered close contacts, the tourism agency said Monday.

The tourists, all Thai nationals, got tested after the individual complained of a sore throat on Monday, according to Kyodo News. The tour has been canceled.

The individual, who has no fever, is expected to quarantine in a repurposed facility for people who have tested positive for COVID-19. The travel agency that hosted the tour is coordinating with authorities to deal with the situation.

The three close contacts are currently isolating at a separate hotel, the agency said. They received a negative result in an antigen test and do not have any symptoms.

Japan plans to open its borders to international tourists on escorted tours from June 10 — the first time they will have been conducted in more than two years. The nation began accepting foreign tourists as part of a trial of such package tours on Tuesday last week.