On Wednesday, the initial 14-day quarantine aboard a coronavirus-stricken cruise ship docked in Yokohama, Japan, officially ended. But the grueling saga seems far from for over for the ship’s 3,711 passengers and crew.

As the quarantine time ran out, Japanese officials were still reporting dozens of new cases of COVID-19 aboard. As of Wednesday, the number of coronavirus infections linked to the ship total 621—by far the largest cluster of COVID-19 infections anywhere outside of China. The next-largest cluster outside of China is in Singapore, which has 84 confirmed cases.

Japanese health officials are facing international criticism for their handling of the quarantine on the ship, the Diamond Princess. The quarantine was intended to curb the spread of disease by keeping people aboard, isolated from each other and from the public on land. But as cases mounted over the two weeks, it became clear that the control efforts only enabled the new coronavirus to spread. In fact, the 621 cases include at least three Japanese health officials, who were there to support the quarantine efforts but ended up becoming infected themselves.