Kim Yo-jong, the sister of North Korean leader Kim Jong-un, on Wednesday blamed South Korea for the COVID-19 outbreak in the North, and threatened the “extermination” of South Korean authorities.

According to the North’s Korean Central News Agency, Kim Yo-jong blamed “unusual objects” of South Korean origin -- anti-North Korea leaflets sent from the South -- for COVID-19 outbreaks in North Korea at a disease control meeting presided over by her brother.

“The national crisis we have experienced is clearly caused by the frenzy of the enemies who attempt to crush our country by using the global health crisis as an opportunity,” said Kim.

She said that as the outbreak began near the inter-Korean border, the obvious conclusion was to suspect objects found in the region as the source of the virus.

She went on to issue a threat, saying that Pyongyang will “answer by exterminating not only the virus but South Korean authorities” should “dangerous actions that can lead to inflow of virus” continue.

Regarding Kim’s threat, Col. Kim Jun-rak, spokesperson for South Korea’s Joint Chiefs of Staff, said that they are firmly prepared for any situation in a regular briefing on Thursday.

Meanwhile, the North Korean leader Kim Jong-un has declared the perfect extermination of the COVID-19 virus at the same meeting.

“I solemnly declare the victory in the maximum emergency anti-epidemic campaign for exterminating the novel coronavirus that had made inroads into our territory and protecting the lives and health of the people,” he said.

North Korea had acknowledged having a COVID-19 outbreak on May 12, and claimed to have zero fever patients since July 29, after the total peaked at nearly 400,000 on May 15.