China tightens exit rules , restricts travel over tech, national security concerns

China tightened travel curbs on Tuesday as new exit-and-entry rules took effect, barring citizens deemed a ​potential threat to national technology security from leaving the country.

Chinese are generally free to travel, unlike during the height of the Cold War when few were able to venture overseas, but the government has long kept close watch on the travel plans of those it considers could present a security risk.