Since the division of the peninsula, North Korea has used subversion and sabotage against South Korea as part of its effort at reunification. Historically, the military part of this effort has centered on military infiltration, border incidents designed to raise tensions, and psychological warfare operations aimed at the South Korean armed forces. Infiltration by North Korean military agents was commonplace in South Korea after the armistice in 1953. Over time, however, there were clear shifts in emphasis, method, and apparent goals. P'yongyang initially sent agents to gather intelligence and to build a revolutionary base in South Korea.

The 1960s saw a dramatic shift to violent attempts to destabilize South Korea, including commando raids and incidents along the DMZ that occasionally escalated into firefights involving artillery. The raids peaked in 1968, when more than 600 infiltrations were reported, including an unsuccessful commando attack on the South Korean presidential mansion by thirty-one members of North Korea's 124th Army Unit. The unit came within 500 meters of the president's residence before being stopped. During this incident, twenty-eight infiltrators and thirty-seven South Koreans were killed. That same year, 120 commandos infiltrated two east coast provinces in an unsuccessful attempt to organize a Vietnamese-type guerrilla war. In 1969 over 150 infiltrations were attempted, involving almost 400 agents. Thereafter, P'yongyang's infiltration efforts abated somewhat, and the emphasis reverted to intelligence gathering, covert networks, and terrorism.

Subsequent incidents of North Korean terrorism focused on the assassination of the South Korean president or other high officials. In November 1970, an infiltrator was killed while planting a bomb intended to kill South Korean president Park Chung Hee at the Seoul National Cemetery. In 1974 a Korean resident of Japan visiting Seoul killed Park's wife in another unsuccessful presidential assassination attempt.

From the mid-1970s to the early 1980s, most North Korean infiltration was conducted by heavily armed reconnaissance teams. These were increasingly intercepted and neutralized by South Korean security forces.

After shifting to sea infiltration for a brief period in the 1980s, P'yongyang apparently discarded military reconnaissance in favor of inserting agents into third countries. For example, on October 9, 1983, a three-man team from North Korea's intelligence services attempted to assassinate South Korean president Chun Doo Hwan while he was on a state visit to Rangoon, Burma. The remotecontrolled bomb exploded prematurely. Chun was unharmed, but eighteen South Korean officials, including four cabinet ministers, were killed and fourteen other persons were injured. One of the North Korean agents was killed, two were captured, and one confessed to the incident. On November 29, 1987, a bomb exploded aboard a Korean Air jetliner returning from the Middle East, killing 135 passengers on board. The bomb was placed by two North Korean agents. The male agent committ300 tted suicide after being apprehended. The female agent was turned over to South Korean authorities she confessed to being a North Korean intelligence agent and revealed that the mission was directed by Kim Jong Il as part of a campaign to discredit South Korea before the 1988 Seoul Olympics. In the airliner bombing, North Korea broke from its pattern of chiefly targeting South Korean government officials, particularly the president, and targeted ordinary citizens.

Data as of June 1993