On November 23, 2010, the North Korea military opened fire at Yeonpyeong island of South Korea, claiming that a South Korean artillery exercise as an attack against the North. The North Korea military began the bombardment at 14:34, and fired around 170 artillery shells and rockets to the island, hitting both military and civilian residents targets until it stopped the fire at 15:41. The shelling damaged 38 spots of the island, damaged 21 civilian houses, killed two South Korean marines, two civilians, injured sixteen soldiers, three civilians. South Korea military also fired back around 80 artillery to the North. The bombardment was the first artillery engagement between North Korea and South Korea since the Korean War's armistice in 1953. The United Nations declared it one of the most serious incidents since the end of the Korean War. Former US ambassador to UN Bill Richardson said tensions had escalated to become "the most serious crisis on the Korean peninsula since the 1953 armistice, which ended the Korean War". North Korea's motives for the attack are still unclear until today. However, some experts assume it was partly related to Kim Jong-un's appointment as the successor to Kim Jong-il. The Korean War is often called "the Forgotten War" though it was the biggest international war since World War II. The impacts of the Korean War still linger for almost 70 years, and the war has not ended but is only suspended.