South Korea fired tens of artillery rounds towards North Korea on August 20 after the North fired a projectile towards a South Korean loudspeaker that had been blaring anti-Pyongyang broadcasts, the defence ministry in Seoul said. North Korea did not immediately respond to the South's shots, it said, as tensions rose on the peninsula.

Tension between the two Koreas has risen since early this month when landmine explosions in the Demilitarised Zone (DMZ) of the border wounded two South Korean soldiers. Seoul accused North Korea of laying the mines, which Pyongyang has denied.

Seoul then began blasting anti-North Korean propaganda from loudspeakers on the border, resuming a tactic that both sides had halted in 2004.

North Korea on Saturday demanded that the South halt the broadcasts or face military action, and on August 17 began conducting its own broadcasts.

The exchange of fire on August 20 came amid ongoing annual joint U.S. and South Korean military exercises, which began the same day and which North Korea condemns as preparation for war.

Bomb blast during Korean war 1950-53 | Source: Wikipedia

The two Koreas have remained in a technical state of war since the 1950-1953 Korean War ended in a truce, not a peace treaty.

South Korea's won currency weakened in non-deliverable forward trading on the reports of the firing, which came after onshore spot trading had closed. The 1-month contract rose as high as 1,192.7 won per dollar from around 1,189.8 earlier.