Lee Man-hee, the normally reclusive head of the Shincheonji church, bowed low twice at a hastily arranged news conference.
“We did our best but weren’t able to contain it fully,” the 88-year-old, wearing a white face mask, told assembled journalists.
“We immediately cooperated, but there’s really nothing I can say,” Lee said. Public health officials say the church has hindered efforts to contain the spread of the virus.
Lee, who claims he is the second coming of Jesus Christ, has previously called coronavirus the "devil's deed" to stop his church’s growth.
South Korea has more coronavirus cases than any country outside of China. On Monday, authorities reported 599 new cases, for a total of 4,335, while 26 people have died.
Worldwide cases of and deaths from COVID-19, the disease caused by coronavirus.
More than half of the cases are linked to a branch of the Shincheonji church in Daegu, a city in the southeast of South Korea.
The Shincheonji church is viewed as a cult within South Korea and by mainstream Christian organizations. People shouted “cult” and called on the church to disband as Lee gave his press conference outside a church facility in Gapyeong, about 35 miles out of Seoul.
It has been accused of making it more difficult for South Korean health authorities to track the spread of the outbreak by withholding its members' names.
Lee's press conference came after the local government in Seoul filed a criminal complaint with prosecutors asking for an investigation into Lee and other church leaders on charges including murder.
Park Won-soon, Seoul's mayor, said that preventive measures could have saved lives.
“The situation is this serious and urgent, but where are the leaders of the Shincheonji, including Lee Man-hee, the chief director of this crisis?” Park wrote on Facebook on Sunday.