South Korean authorities identified 79 new novel coronavirus cases yesterday — the most in a single day since April 5.

Sixty-eight of those were locally transmitted, with the majority found in Seoul, the province that surrounds the capital, Gyeonggi, and the city of Incheon.

Vice Health Minister Kim Gang-lip said that 54 of the patients identified Wednesday were traced to a logistics center in Bucheon, a satellite city 25 minutes from downtown Seoul. It’s possible that the Bucheon cases are linked to a cluster identified in Itaewon, a popular nightlife district in Seoul, but the investigation is ongoing, an official at the Health Ministry said.

More than 4,150 people connected to the Bucheon cluster have been put under quarantine and 83% of them have been tested, Kim said. The rest will be tested today.