A North Korea expert has claimed that deaths related to COVID-19 occurred in the North's Wonsan and Hamhung regions in May.

Kang Young-sil, a researcher at the Research Center of North Korean Science and Technology, made the claims in the Korea Development Institute’s(KDI) journal on Monday, based on internal documents from the North.

According to the documents, COVID-19 deaths were reported in Sariwon, Sinuiju, Wonsan, Hamhung, Chongjin, Hoeryong, and the provinces of Gangwon, North Hamgyong and South Hamgyong.

No deaths were reported in Pyongyang, Gaeseong or Pyongsong.

This is in contrast to the North's official claim that there haven't been any confirmed cases or coronavirus-linked deaths within its borders, thanks to border lockdowns and strict quarantine.

The paper said as of May, some 20-thousand people were quarantined in North Korea for suspected COVID-19 contraction, 14-thousand of whom were in North Hamgyong Province.