Seoul, South Korea - North Korea has shut down its largest unofficial market in a sign that the Communist government was intent on quashing, or at least better controlling, market activities that it had tolerated for years, Seoul-based organizations monitoring the country said last week. The market, on the outskirts of Pyongyang, was closed sometime in June and vendors were dispersed to two or three smaller nearby markets, according to the Network for North Korean Democracy and Human Rights, or NKNet, which says it monitors the North using informants from inside the country. Such markets began opening in the 1990s when a multiyear famine loosened the government's control on the food supply.