SEOUL, South Korea (AP) — South Korea has reported more than 500 new coronavirus cases for the third straight day, the speed of viral spread unseen since the worst wave of the outbreak in spring.

The 504 cases reported by the Korea Disease Control and Prevention on Saturday brought the national caseload to 33,375, including 522 deaths.

Around 330 of the new cases came from the densely populated Seoul metropolitan area, home to about half of the country’s 51 million population, where health workers are struggling to stem transmissions linked to hospitals, schools, saunas, gyms and army units.

Infections were also reported in other major cities including Daegu, which was the epicenter of the country’s previous major outbreak in late February and March.

The recent spike in infections came after the government eased social distancing restrictions to the lowest levels in October to support a weak economy, allowing high-risk venues like nightclubs and karaoke bars to reopen and spectators to return to sports.

Officials reimposed some of the restrictions this week and could be forced to clamp down on economic activities further if transmissions don’t slow.

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