North Korea is rushing to complete a cluster side of high-rise apartments in Sinuiju on the Chinese border.

"I wonder what they're doing even though the borders are sealed," a local in Dandong on the Chinese side of the Apnok or Yalu River said.

Five or six 15-story apartment buildings are under construction right on the river bank and the raw structures are already finished.

North Korea sealed its borders at the outbreak of the coronavirus pandemic early last year. The road and railway between Dandong and Sinuiju, which used to carry 70 percent of trade volume between the two countries, are closed, though some farming supplies like fertilizer have been imported by sea.

Apartments are under construction in Sinuiju as seen from Dandong, China on Aug. 28.

Yet the high-risers, which are a rarity outside Pyongyang, keep going up, perhaps in anticipation of the end of the pandemic. Rumors circulating in Dandong say North Korean leader Kim Jong-un ordered them to be erected because he was embarrassed by the contrast between wealthy Chinese Dandong and shabby low-rise Sinuiju.

The contrast is highlighted by a cluster of high-risers of 40 stories or more on the Dandong side. A Sinuiju resident of Chinese descent, who has been staying in Dandong since borders were closed, said, "They've demolished many one-story houses to build the apartments in Sinuiju. North Korea must be carrying out the construction with building materials from China because they don't have them there."

Another Dandong resident said, "One change is that the lights are on in and around the construction site." All of Sinuiju, except a lighting tower in the railway station plaza, used to be blacked out at night due to the North's chronic power shortage, but now some street lights can be spotted across the water, probably powered by solar panels recently imported from China.

Tight security prevents ordinary North Koreans from getting too close to the river in case they flee across, so the apartments on the river bank must be either a Potemkin village or designed with Chinese residents in mind. The nearby Yalu River Broken Bridge is a moderately famous tourist spot for Chinese people.