South Korea has begun annual naval exercises off its east coast as tensions with North Korea remain high.

The drills beginning Wednesday and ending Saturday are on the opposite coast from the disputed sea border where North Korea shelled a front-line island a month ago.

But South Korea’s military is on high alert following firing exercises from the island Monday.

A Joint Chiefs of Staff officer says navy ships will fire artillery and conduct anti-submarine exercises. The officer spoke on condition of anonymity, citing department rules.

Most of the Koreas’ recent military skirmishes have taken place near the western sea frontier drawn by U.N. forces at the close of the 1950—53 Korean War. North Korea rejects the boundary.

Keywords: Korean tensions

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