SEOUL: Authorities in the North Korean capital Pyongyang have ordered a five-day lockdown due to rising cases of an unspecified respiratory illness, the Russian embassy and Seoul-based NK News reported on Wednesday, citing a government notice.

The notice, shared by the embassy on its Facebook page, said that a "a special anti-epidemic period has been established" and it called on foreign delegations to keep employees inside. The order also called for individuals to measure their temperatures four times a day and report the results to a hospital by phone.

The notice made no mention of COVID-19 though cited an "increase in winter cases of recurrent flu and other respiratory diseases".

The lockdowns were first reported by South Korea's NK News, which monitors secretive North Korea.

On Tuesday, the website reported that Pyongyang residents appeared to be stocking up on goods in anticipation of stricter measures. It was unclear if other areas of the country had imposed new lockdowns.

North Korea acknowledged its first COVID-19 outbreak last year, but by August had declared victory over the virus.

It never confirmed how many people caught COVID, apparently because it lacks the means to conduct widespread testing.

Instead, Pyongyang reported daily numbers of patients with fever, a tally that rose to some 4.77 million, out of a population of about 25 million. But it has not reported such cases since July 29.

State media have continued to report on anti-pandemic measures to battle respiratory diseases, including the flu, but have yet to report on the lockdown order.

On Tuesday, state news agency KCNA said the city of Kaesong, near the border with South Korea, had intensified public communication campaigns "so that all the working people observe anti-epidemic regulations voluntarily in their work and life".