An apartment building under construction in Pyongyang collapsed last week, prompting senior executives to offer a rare public apology, state media and Seoul officials said Sunday.

The disaster took place on May 13 in the Pyongchon district, where the construction of the 23-story building was nearing completion, according to the official Korean Central News Agency. No death toll was reported though it described the accident as “serious.”

As many as 92 households had already moved in, an official at Seoul’s Unification Ministry said, raising the possibility of significant casualties. “A considerable number of people are likely to have died,” the official said on customary condition of anonymity.

“The construction of the apartment building was not done properly and officials supervised and controlled it in an irresponsible manner,” the KCNA said.

People’s Security Minister Choe Pu-il apologized to the victims and district residents, with the Rodong Sinmun, a mouthpiece of the governing Workers’ Party, carrying a photo of an unidentified official bowing his head before the crowd. Other officials also met with the bereaved families, including Sonu Hyong-chol, general officer of the Korean People’s Internal Security Forces; Cha Hui-rim, chairman of the Pyongyang City People’s Committee; and Ri Yong-sik, chief secretary of the party’s Pyongchon District Committee. 

The accident caused leader Kim Jong-un to “sit up all night, feeling painful” and instruct leading officials of the party, state and army to “rush to the scene, putting aside all other affairs, and command the rescue operation to recover from the damage as early as possible,” Kim Su-gil, a party secretary in Pyongyang, was quoted as saying by the KCNA.

Though the search operation ended Saturday, a national emergency response team was set up to facilitate the rescue efforts and the treatment of the injured, it added.

The report marks a rare admission of a tragic accident by the reclusive, erratic regime, which has long claimed infallibility across the board.

The fallen apartment building was part of an ambitious initiative to “modernize” Pyongyang, launched in 2002 by late strongman Kim Jong-il. The plan called for building 100,000 housing units, including some 2,700 in high-rises, along with parks and monuments across 13 districts in the capital city.

The revelation reflects its efforts to prevent public anger at home, while flaunting its credentials as a responsible, legitimate government after lambasting the South for its botched response to the recent ferry disaster, observers say.

In another exception, the communist country not only sent out dispatches but also requested assistance from Seoul and the international community in the wake of a 2004 blast at the Ryongchon train station in the northwestern province of North Pyongan.

Yet Pyongyang did not release the full extent of the damage. A U.N.-led fact-finding mission estimated that the explosion killed at least 150 people, wounded 1,300 and wreaked havoc on around 8,100 housing units.

“North Korea does not make public its major internal accidents other than flood damage, though accidents frequently occur at construction sites given its reliance on the prefabrication method and labor,” the Unification Ministry said.

By Shin Hyon-hee (heeshin@heraldcorp.com)