Three Czech Olympic athletes, and two other members of their Olympic delegation, tested positive for COVID and were being quarantined in Tokyo on Thursday. And officials are investigating whether the outbreak was caused by a very lax chartered flight the team took to Japan, in which an unvaccinated doctor was on board. There were 42 people on the flight—14 were athletes—and some passengers weren’t wearing masks. Vlastimil Voráček, an unvaccinated orthopedist, is one of those who tested positive upon arrival. “Everywhere we convince people to be vaccinated. And here the doctor of our delegation is not vaccinated,” Czech Prime Minister Andrej Babiš said. The Czech Olympic Committee said they’re working with Olympic organizers to contain the spread and moved some team members out of the Olympic Village.