SEOUL, South Korea (AP) — South Korea has reported its largest daily increase in coronavirus infections on Christmas Day, as the prime minister pleaded for vigilance to arrest a viral surge that has worsened hospitalization and deaths.

The 1,241 new cases confirmed by the Korea Disease Control and Prevention Agency on Friday brought the country’s caseload to 54,770. Seventeen COVID-19 patients died in the past 24 hours, bringing the death toll to 773.

More than 870 of the new cases were from the greater capital area, home to half of the country’s 51 million population, where nearly 300 infections so far have been linked to a huge prison in Seoul. Clusters have been popping up from just about everywhere in recent weeks, including hospitals, long-term care facilities, churches, restaurants and army units.

The country has been expanding its mass testing program to slow the rate of transmissions and more than 118,000 tests were conducted on Thursday alone. Officials are also clamping down on private gatherings through Jan. 3, shutting down national parks and ski resorts and setting fines for restaurants if they receive groups of five people or more.

“The last week of the year that begins with Christmas is normally a time where people gather and share their affection with one another, but it’s hard to see that this year in any parts of the world,” Prime Minister Chung Sye-kyun said during a virus meeting.

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