WORLD IN BRIEF : TIBET : China Adds Security on Key Anniversary

China increased security patrols and virtually sealed off Tibet on the first anniversary of the imposition of martial law. Travel agents in Chengdu, China’s main gateway to Lhasa, the Tibetan capital, said tours have been canceled and that travel permits will not be issued until March 15. Despite the tension, there were no reports of renewed protests by Tibetan nationalists. Authorities did allow Tibet’s Buddhist monks to continue a major prayer festival that has been the occasion of anti-Chinese protests in the past. The 10-day festival, which began last week, provoked last year’s anti-Beijing riots that led to martial law.