Lee Man-hee, leader of the Shincheonji Church of Jesus, bows during a press conference at a facility of the church in Gapyeong on March 2, 2020.

The mayor of Seoul has sued key leaders of the Shincheonji religious group at the center of South Korea's sudden surge in the number of confirmed cases for the new coronavirus.

Mayor Park Won-soon said on Facebook he was suing the key leaders of Shincheonji "for murder, injury and violation of prevention and management of infectious diseases," according to a translation from NBC News.

Park reported 12 leaders to the Seoul Central District Prosecutor's Office on Sunday.

South Korea has the highest number of infections outside mainland China. On Monday morning, the total number of cases in South Korea stood at 4,212, and 22 had died from the infection. Just two weeks earlier, the number of cases stood at around 30.

Contributing to the exponential rise in cases was the city of Daegu, and specifically, the secretive religious group called Shincheonji, according to the country's Centers for Disease Control and Prevention. As of Sunday morning, the group accounted for almost 60% of all cases in the country, with most of them centered in Daegu.

The flu-live virus, officially named COVID-19 by the World Health Organization last month, has infected over 87,000 globally.

"We can handle the COVID-19 situation as soon as possible only when we forcefully investigate the twelve branch heads of the Shincheonji sect along with Lee Man Hee, the Chairman of the sect," Park said in his Facebook post on Sunday. Lee is the founder and spiritual leader of Shincheonji Church of Jesus.

"The prosecutors need to carry out a rigorous investigation and make sure it leads to a strict punishment on the Shincheonji leadership that is at the center of this crisis," Park added in a separate statement posted to the mayor's office website.

Lee apologized on Monday at a news conference for his group's inability to stop the spread of the virus and called the epidemic a "great calamity," Reuters reported.