SEOUL, South Korea — North Korea has blocked the windows of high-rise apartments in Pyongyang, its showcase capital city, to prevent residents from looking down, or spying, on the party and government buildings where its top leader, Kim Jong-un, conducts business, a news report said Friday.

Under Mr. Kim, North Korea has engineered a building boom in Pyongyang, raising a slew of high-rise apartment buildings and doling out the housing to nuclear and missile scientists and other elites. But the building boom appears to have created a problem: Residents of top floors of the buildings can literally look down on state buildings where Mr. Kim, the North’s godlike totalitarian leader, and other party elites work.

In July, Daily NK, a Seoul-based website that specializes in North Korea news, reported that officials from the Ministry of State Security, the North’s secret police, had visited top-floor apartments commanding a view of key government facilities in central Pyongyang and installed concrete and other fixed screens blocking the windows.

“The measures were designed to stop people from taking pictures of key state facilities from top-floor apartments and sending them outside North Korea,” Daily NK said, quoting anonymous sources inside North Korea. “Besides, they didn’t want people to look down on the Workers’ Party and other key state facilities.”