South Korea's government on Friday called on health authorities to act strongly against any move to impede their efforts to curb the spread of the new coronavirus.

President Moon Jae-in called for "stern measures," including criminal charges, for anyone who tries to "hamper epidemiological studies" while visiting Seoul city government's office to check the city's quarantine operations.

"If necessary, relevant laws should be enforced, including apprehension on site or seeking an arrest warrant," he said.

His comments came after some local churches were accused of not cooperating with the state efforts to trace and isolate potential COVID-19 patients.

Health officials visited the headquarters of the Sarang Jeil Church in Seoul on Thursday evening to secure the full list of its congregation. However, they returned empty-handed in the early hours of the following day after more than 10 hours of confrontation with church officials.

The church has emerged the second biggest cluster after the outbreak in the Shincheonji Church of Jesus this spring, with 732 cases traced to it. The authorities believe the list the church had given was not complete.

Pastor Jun Kwang-hoon of the church took part in a massive anti-government rally attended by approximately 20,000 people at Gwanghwamun Square, central Seoul, on Saturday, leading church members and his political followers from around the country. It is not known exactly how many of the church congregants participated in the event. Jun and several of his aides tested positive after the rally.

"The core principle" of the country's efforts to fight against COVID-19 is, the president said, "swiftly detecting and testing close contacts and isolating the confirmed patients, but things that interfere with (those efforts) have been done systematically."

He added, "Obstructive activities are done physically on the scene (of quarantine operations), or through all-out misinformation campaigns."

While he didn't specify what misinformation he was referring to, ultra-right commentators, including pastor Jun of Sarang Jeil, have been claiming on the internet that the virus has been purposely spread in the church as an act of terrorism to oppress freedom of religion.

The president also emphasized the need for the Seoul metropolitan government to take fast action by enforcing law and order in an "unflinching" and "preemptive" manner and by asking for cooperation from the police and the central government, if necessary.

When it comes to the fight against the pandemic, "state authority should be exercised in a way to protect people's lives" and safety, he said, while its use should be minimized in normal times not to "violate the people's basic human rights."

"This is the biggest crisis we've faced since the COVID-19 pandemic started in the country," he said, adding that "if quarantine efforts fail in Seoul, they will do so in the rest of the country."

The ministers of justice and interior held a separate press briefing in the afternoon, echoing the sense of urgency expressed by the president and detailing the enhanced policy guidelines on the matter.

Justice Minister Choo Mi-ae said the government will seek the maximum penalty allowed in the relevant laws to punish obstruction of justice on the quarantine front.

On the detailed behaviors that would bring stern actions from the government, the minister cited violating no-assembly orders, interfering with contact tracing efforts by submitting false information, assaulting health officials, purposely evading state contacts and running away, refusing to get tested and instigating anti-government sentiment.

"The whole country should work together to overcome this difficulty. We should not allow any more spread (of the virus)," she said. "I urge you to trust the government and health authorities and actively cooperate with the quarantine guidelines." (Yonhap)