North Korea and South Korea have reportedly traded artillery fire Nov. 23 across the disputed Northern Limit Line (NLL) in the Yellow Sea to the west of the peninsula. Though details are still sketchy, South Korean news reports indicate that around 2:30 p.m. local time, North Korean artillery shells began landing in the waters around Yeonpyeongdo, one of the South Korean-controlled islands just south of the NLL. North Korea has reportedly fired as many as 200 rounds, some of which struck the island, injuring at least 10 South Korean soldiers, damaging buildings and setting fire to a mountainside. South Korea responded by firing some 80 shells of its own toward North Korea, dispatching F-16 fighter jets to the area and raising the military alert to its highest level. South Korean President Lee Myung Bak has convened an emergency Cabinet meeting, and Seoul is determining whether to evacuate South Koreans working at inter-Korean facilities in North Korea. The barrage from North Korea was continuing at 4 p.m. Military activity appears to be ongoing at this point, and the South Korean Joint Chiefs of Staff are meeting on the issue. No doubt North Korea's leadership is also convening. The North Korean attack comes as South Korea's annual Hoguk military exercises are under way. The exercises — set to last nine days and including as many as 70,000 personnel from all branches of the South Korean military — span from sites in the Yellow Sea including Yeonpyeongdo to Seoul and other areas on the peninsula itself. The drills have focused in particular on cross-service coordination and cooperation in recent years. Low-level border skirmishes across the demilitarized zone and particularly the NLL are not uncommon even at the scale of artillery fire. In March, the South Korean naval corvette ChonAn was sunk in the area by what is broadly suspected to have been a North Korean torpedo, taking tensions to a peak in recent years. Nov. 22 also saw South Korean rhetoric about accepting the return of U.S. tactical nuclear weapons to the peninsula, though the United States said it has no plans at present to support such a redeployment. While the South Korean reprisals — both artillery fire in response by self-propelled K-9 artillery and the scrambling of aircraft — thus far appear perfectly consistent with South Korean standard operating procedures, the sustained shelling of a populated island by North Korea would mark a deliberate and noteworthy escalation. The incident comes amid renewed talk of North Korea's nuclear program, including revelations of an active uranium-enrichment program, and amid rumors of North Korean preparations for another nuclear test. But North Korea also on Nov. 22 sent a list of delegates to Seoul for Red Cross talks with South Korea, a move reciprocated by the South, ahead of planned talks in South Korea set for Thursday. The timing of the North's firing at Yeonpyeongdo, then, seems to contradict the other actions currently under way in inter-Korean relations. With the ongoing leadership transition in North Korea, there have been rumors of discontent within the military, and the current actions may reflect miscommunications or worse within the North's command-and-control structure, or disagreements within the North Korean leadership.