SEOUL, South Korea — It was sad enough when the bodies of Han Sung-ok and her 6-year-old son were found in their $74-a-month apartment in Seoul in July, two months after they had died.

But the story became national news after it emerged that Ms. Han, 42, was a North Korean who had fled famine in her homeland, and that the two had died alone and impoverished in one of Asia’s richest cities.

Their bodies were so decomposed that the cause of death could not be determined, according to the authorities. But several South Korean news outlets have reported that they died of starvation, and officials have not disputed those reports. The news channel that broke the story last month quoted an unidentified police officer as saying that there was no other possible explanation.

The deaths have been a shocking reminder of the hardships faced by many North Koreans in the South, as they try and sometimes fail to adjust to a radically new life. Since the news became public, thousands have visited a mourning station built for Ms. Han and her son, Kim Dong-jin, in central Seoul, laying white chrysanthemums in front of portraits of them.