In a symbolic display of anger, North Korea on Tuesday blew up the northern section of unused roads that once linked it with the South, with the rivals exchanging threats days after the North claimed that its rival flew drones over its capital Pyongyang.

The roads’ choreographed demolition underlines North Korea’s growing anger against South Korea’s conservative government. North Korean leader Kim Jong Un has vowed to sever relations with South Korea and abandon the goal of achieving peaceful Korean unification. Observers say it’s unlikely Kim will launch a preemptive, large-scale attack on South Korea because of fear that an almost certain massive retaliation by the more superior forces of the US and South Korea.