The eldest son of former North Korean leader Kim Jong-il has not been seen in his second home in Macau since his half brother Kim Jong-un became the new leader of the North.
The head of an association for Korean residents in Macau, Lee Dong-sup, said Kim Jong-nam disappeared from Macau since his brother came to power late last year.
Lee, who has lived in Macau since 1982, told the Chosun Ilbo, "I got to know Kim Jong-nam around 2000 due to a chance encounter and kept in touch with him, but I haven't seen him so far this year."
Kim Jong-nam used to communicate with Japanese media until the death of his father but has not definitely been spotted since January, when he was seen waiting in Beijing for a flight to Macau.
There have been unconfirmed sightings in a luxury hotel in Singapore. In the past Kim Jong-nam, who was passed over for the leadership, has voiced his opposition to the hereditary transfer of power in North Korea.
A North Korean agent who was arrested in South Korea last month told interrogators he was ordered in July 2010 to assassinate Jong-nam.
Lee said Jong-nam's wife and 13-year-old daughter still live in Macau.
Until a few years ago, Macau served as the financial source to fund luxury goods purchases by the Kim dynasty and as a base station for the North's espionage activities.
"U.S. financial sanctions (in 2006) dealt a fatal blow to North Korea's overseas missions, so it probably had no choice but to give up its operations in Macau," Lee speculated.
He added that the number of North Koreans in Macau has shrunk from 160 in 2006 to around 30.