SEOUL, South Korea — Health officials in South Korea reported 279 new coronavirus cases on Sunday, warning of a resurgence of infections, many linked to a church that has vocally opposed President Moon Jae-in.
South Korea had battled the epidemic down to two-digit daily caseloads since April. But the number of new cases has soared recently, with 103 on Friday and 166 on Saturday, most of them worshipers at the Sarang Jeil Church in Seoul, the capital, and another church in the surrounding province of Gyeonggi.
The church outbreaks have alarmed health officials. Tightly packed, fervent prayer services in some South Korean churches have made them particularly vulnerable to the virus.
When South Korea was hit by its first wave of the coronavirus in late February and early March, the epidemic spread mainly from the Shincheonji Church of Jesus in the central city of Daegu, about 150 miles southeast of Seoul. The church has been accused of being a cult by more mainstream churches. During the first wave of infections, the daily caseload across the country was as high as 909.
In the past four days, the Sarang Jeil Church alone has reported at least 193 cases among its members and contacts, the Seoul metropolitan government said. President Moon on Sunday warned of a surge in infections in coming days as health officials rush to test thousands of church members and their contacts. He called the crisis at Sarang Jeil the biggest challenge faced by health officials since the Shincheonji outbreak five months ago.
The Sarang Jeil Church has been as controversial as Shincheonji.
Its chief pastor, the Rev. Jun Kwang-hoon, has been a driving force behind largely Christian conservative rallies against Mr. Moon in central Seoul in recent months. Mr. Jun openly accuses Mr. Moon’s liberal government of trying to “communize” South Korea and urges a public uprising to “oust” the president from office.
Mr. Jun was arrested in February on charges of violating election laws ahead of April parliamentary elections. He was accused of asking participants at his rallies to support specific political parties before the official election period had begun. Since his release on bail in April, he has continued his political activism, calling for a large anti-Moon rally in Seoul on Saturday.
The Seoul city government banned the rally and temporarily shut down his church, citing fears that a large gathering would help spread the virus. More than 4,000 members of Mr. Jun’s church were also ordered to self-isolate for two weeks and test for the virus.
But Mr. Jun ignored the order, attending a rally in central Seoul on Saturday organized by another antigovernment conservative group. He claimed that the outbreak in his church had been caused by a “terrorist” attack aimed at crippling its political activism.
“They poured the virus on our church,” he said during the rally, without specifying who he was referring to.
Health officials said his accusation was not worth commenting on. Mr. Jun is known for giving rousing speeches filled with provocative and unsubstantiated claims.
Mr. Jun said he had urged his congregants not to join the rally on Saturday and to stay home. But the local news media reported that members of his church were among thousands of antigovernment protesters on Saturday, some of them not wearing masks.
Mr. Moon on Sunday called their participation in the rally an “unpardonable act.”
“Many of those who needed to be in self-isolation turned out in street protests, raising the serious possibility that they have spread the virus to protesters who came from around the country,” Mr. Moon said on his Facebook page. “This is a clear challenge against the disease-prevention system of the state and an unpardonable act against the safety of the people.”
Mr. Moon vowed to “take decisive actions, including coercive measures” against Mr. Jun’s church. Also on Sunday, the Seoul city government said it would sue Mr. Jun for violating disease-control laws by spreading false rumors about the epidemic and ignoring a government order to self-isolate.
Thousands of protesters, many of them older, attended the anti-Moon rally on Saturday, ignoring rain and official pleas to stay home amid the rise in coronavirus infections. On the same day, Kwon Jun-wook, a deputy director of the government’s Central Disease Control Headquarters, warned of “early signs of a large-scale resurgence of the virus.”
Over the weekend the government tightened social-distancing rules in Seoul and Gyeonggi Province, which have a combined population of roughly 20 million people. Under the new rules, spectators will be barred from professional baseball and soccer games. The authorities have the power to ban large gatherings and shut down high-risk facilities such as karaoke rooms, nightclubs and buffet restaurants if they fail to enforce heightened preventive measures, including temperature checks, keeping rosters of all visitors and requiring them to wear masks.
Virus fears also prompted South Korea and the United States on Sunday to delay an annual joint military drill by two days, rescheduling it to begin on Tuesday. The allies decided to postpone the exercise after a South Korean Army officer who was expected to participate in the drill tested positive.
So far, health officials have been reluctant to designate churches as high-risk facilities for fear they might be accused of undermining freedom of religion. But even before the outbreak in Mr. Jun’s church, small clusters of infections have continued to erupt in churches in recent months.