| South Korea's military tightened roadblocks and traffic checkpoints north of Seoul after finding signs of possible infiltration by North Korean agents on Tuesday, officials said. South Korean border guards found a hole in the wire fence that forms the southern boundary of the 2.5-mile wide Demilitarized Zone that separates the two Koreas, a Defense Ministry spokesman said, speaking on customary condition of anonymity. The 16- by-12-inch hole was discovered early Tuesday near Yeoncheon, a border town some 40 miles north of Seoul. The increased security along the roads between Yeoncheon and Seoul came as U.S. Secretary of States Colin Powell was visiting South Korea to discuss a strategy for restarting stalled talks on North Korea's nuclear weapons programs. |