South Korea reported 1,030 new coronavirus cases Sunday, a record high for a second day in a row as the country struggles to tackle a third wave of infections.
The country had previously been held up as a model of how to combat the pandemic, with the public largely following social distancing and other rules.
But a resurgence centred on the capital and surrounding area has prompted President Moon Jae-in to apologise on Facebook for his administration's failure to contain the latest wave.
On Saturday he called the situation "very grave" after authorities reported 950 new infections, the largest daily increase since the start of the pandemic.
Saturday's record was broken on Sunday with 1,002 new locally transmitted cases, some 786 of which were uncovered in the greater Seoul area — home to half the country's 52 million people.
The weekend numbers followed several days in which authorities reported figures ranging from about 500 to 600.
South Korea's spike came despite the government's tightening of social distancing rules in the capital area earlier this week.
The stricter restrictions include a ban on gatherings of more than 50 people and spectators at sports events. Cafes can serve only takeaways, while restaurants must close by 9 pm, with only deliveries permitted afterwards.
However, authorities said Saturday they may have to tighten the curbs further to the highest level by closing schools, banning gatherings of more than 10 people and allowing only essential employees to offices.
South Korea endured one of the worst early Covid-19 outbreaks outside mainland China, but brought it broadly under control with its "trace, test and treat" approach.
It has never imposed the kind of lockdowns ordered in much of Europe and other parts of the world.
