North Korea said Friday it had lifted a three-week lockdown that was imposed on a border city after a defector believed to be carrying the coronavirus sneaked back into the country. The secretive nation has insisted it has had no cases of COVID-19 — a claim international experts say is unlikely, given the spread of the disease around the world. Authorities in July said they were imposing a lockdown on Kaesong city when a 24-year-old man, arrested after crossing the heavily fortified border from the South, was found to be displaying symptoms of the coronavirus. “It has been proved the situation of anti-epidemic work has been kept and controlled stably”, Leader Kim Jong Un was quoted as saying by the state-run KCNA news agency. Kim “expressed thanks… to the people in the locked-down area for having remained faithful to the measures taken by our Party and government, despite the inconvenience in their living under quarantine”. North Korea’s medical infrastructure is seen as woefully inadequate for dealing with any large-scale outbreak. Pyongyang closed its borders in late January — the first country in the world to do so — in a bid to protect itself against the coronavirus. It imposed tough restrictions that put thousands of people into isolation, but analysts say the country is unlikely to have avoided the contagion.