North and South Korea exchange artillery fire across their mutual border. After North Korean soldiers fire several shots at a military loudspeaker that speaks in high voice against Pyongyang, South Korean troops return ‘dozens of shells” to the suspected source. No casualties are reported. North Korea later warns Seoul in a letter that it will take military action if the South did not stop the loudspeaker broadcasts within 48 hours. In a separate letter, Pyongyang says it is willing to offer an opening to resolve the conflict even though it considers the broadcasts a declaration of war.