SEOUL, South Korea -- In a symbolic display of anger, North Korea on Tuesday blew up the northern sections of unused road and rail routes that once linked it with South Korea, with the rivals exchanging threats days after the North claimed that the South flew drones over its capital Pyongyang.

Tensions have been rising on the Korean peninsula, with Pyongyang saying last week it would further fortify the areas on its side of the border.

North Korea blew up parts of roads and rail lines connecting it with South Korea on Tuesday. The move was largely symbolic, experts said.