North Korean leader Kim Jong Un called an emergency meeting after an individual suspected of having Covid-19 illegally crossed the border from South Korea, state media said on Sunday.
If confirmed, this would be the first case of the disease acknowledged by the Pyongyang government, which has so far maintained the country has recorded no coronavirus infections.
According to state news agency KCNA, Kim convened an emergency meeting on Saturday, after imposing a pre-emptive lockdown on the border town of Kaesong on Friday.
The individual "suspected to have been infected with the vicious virus" defected to the south three years ago and illegally crossed the heavily guarded military demarcation line separating the two countries on July 19, KCNA said.
The agency said that "several medical check-ups" produced an "uncertain result" and that the individual was put under strict quarantine in the border town of Kaesong as a first step.
It wasn't clear whether the individual was specifically tested for Covid-19.
KCNA added that people in Kaesong who have been in contact with the individual and those who have been to the town in the last five days were being "thoroughly investigated, given medical examination and put under quarantine."
The agency said that an investigation into the military unit "responsible for the runaway case" was under way and that "severe punishment" would be administered and "necessary measures" taken.
Early in July, Kim praised the country's six months of anti-epidemic efforts as a "shining success" at a party meeting, though he also said that easing measures too hastily would lead to an "unimaginable and irretrievable crisis," according to KCNA.
Little is known about the reclusive nation's true health situation.
South Korean officials were trying to verify Pyongyang's report about the unauthorized border crossing, Yonhap news agency reported.
Yonhap cited the South Korean military as well as officials at the unification ministry and the presidential office as saying work is under way to check the claim.