China called for emergency talks among six countries mediating the issue of North Korea's nuclear disarmament after N. Korea had placed surface-to-surface missiles on launch pads in the Yellow Sea and also moved several batteries of SA-2 surface-to-air missiles to coastal areas while South Korea started large-scale military drills jointly with the United States.

The tension on the Korean peninsula tightened after North Korea had opened artillery fire on the South's Yeonpyeong Island in the Yellow Sea Tuesday, killing two South Korean marines and two civilians. Sixteen others were injured, along with three civilians. The South retaliated and warned of further strikes. The North later accused South Korea of attacking first.

Western powers condemned the attack and warned against a further escalation. Russia called on both Koreas to refrain from the use of force.

North and South Korea remain technically at war, since no peace treaty was signed following the Korean War in 1953. The Demilitarized Zone between the countries is the most heavily armed border in the world.