At least one person confirmed to have COVID-19 has died in North Korea and hundreds of thousands have shown fever symptoms, state media said on Friday, offering hints at the potentially dire scale of country's first confirmed outbreak of the pandemic.

The data represents an unprecedented admission of an "explosive" outbreak in a country that had previously reported no confirmed cases since the pandemic began, and could mark a grave public health, economic and political crisis for the isolated regime.

Experts said that given North Korea's limited testing capabilities, the numbers released so far probably represent a small fraction of the infections, and could lead to thousands of deaths in one of only two countries in the world without a COVID-19 vaccination campaign. About 187,800 people are being treated in isolation after a fever of unidentified origin has "explosively spread nationwide" since late April, the official KCNA news agency reported.