military action but also to "send a message" to China. On 28 November, South Korean news agency Yonhap News said that North Korea had readied surface-to-surface missiles as the United States and South Korea began military drills. On 21 December, South Korea carried out another live-fire artillery exercise into the same disputed waters just south of the NLL, despite diplomatic opposition from China and Russia. One year after the event the South Korean military presence on the island had been substantially increased with the deployment of more K-9 howitzers, K-10 automatic ammunition re-supply vehicles, 130-millimeter, 36-round, truck-mounted Kuryong multiple rocket launchers and AH-1S Cobra attack helicopters. On 19 May 2013 the South Korean Joint Chiefs of Staff announced that "dozens" of Spike NLOS missiles had been deployed on Baengnyeong Island and Yeonpyeong Island. Speculation on North Korean motives North Korea's motives for the attack were unclear and were the subject of widespread speculation in the South and elsewhere. The North Korean Foreign Ministry stated the North Korean bombardment was retaliation due to South Korea's shelling into sea that North Korea claims as its territorial waters. But some experts suggested that it was at least partly related to Kim Jong-un's appointment as the designated successor to Kim Jong-il, which is believed to have caused tensions within the North Korean leadership. Robert Kelly, an assistant professor at Pusan National University in South Korea, says that Seoul's increasing global stature may have provoked Pyongyang. "My primary guess is that this is a response to the recent international prestige taken by South Korea at the G20. The G20 highlighted North Korean backwardness in the same way that it highlighted that South Korea was a partner of this global elite organization, setting international rules and the North Koreans don't like this", he said. It has also been suggested that the attack was linked to the North's need for food aid. The JoongAng Ilbo newspaper suggested that the attack had been ordered by Kim Jong-il himself. Kim and his son were reported to have visited the Kaemori artillery base, whence many of the North Korean shells were fired, the day before the attack. The Kims had visited a nearby fish farm on 22 November in the company of various senior military figures. According to a source quoted by the newspaper, "Firing artillery across the Northern Limit Line at sea is difficult without a direct order from