North Korea's state media reported today an "unimaginable" accident at an apartment construction site in Pyongyang, which had resulted in an unspecified number of casualties.
South Korean officials said the incident involved the collapse of a 23-storey apartment building, which already had close to 100 families in residence.
It is extremely rare for North Kora to report negative news of this type, and the despatch from the official KCNA news agency included equally rare apologies from top officials.
KCNA said the accident had occurred last Tuesday and was the result of "irresponsible" supervision by officials in charge of the construction.
An "intensive" emergency rescue effort had been carried out to rescue survivors and treat the wounded, it said.
The KCNA did not provide a death toll or elaborate on the cause of the collapse, but said it had left Pyongyang citizens "greatly shocked".
The agency carried lengthy public apologies by senior officials including the Minister of People's Security, Choe Pu-Il.
"(Choe) repented of himself, saying that he failed to find out factors that can put at risk the lives and properties of the people and to take thorough-going measures, thereby causing an unimaginable accident," it said.
A South Korean official, speaking on condition of anonymity, said Seoul was aware of the incident which involved the collapse of a 23-storey apartment complex.
"It is common in North Korea that people move into a new apartment building before construction officially ends," the official told AFP.
The official said 92 families were believed to be living in the collapsed building, and the final death toll was likely to be "considerable".
About 2.5 million people -- mostly political elites including senior party members or those with privileged background -- are believed to live in Pyongyang.
Pyongyang residents are known to enjoy better access to electricity, food, goods and other services than those living elsewhere in the impoverished and isolated country.
