Third Tunnel of Aggression

The Third Tunnel of Aggression (Korean: 제3땅굴; Third Infiltration Tunnel or 3rd Tunnel) is one of four known tunnels under the border between North Korea and South Korea, extending south of Panmunjom. == Background == Only 44 km (27 miles) from Seoul, the incomplete tunnel was discovered in October 1978 following the detection of an underground explosion in June 1978, apparently caused by the tunnellers who had progressed 435 metres (1,427 feet) under the south side of the Korean Demilitarized Zone (DMZ).

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