SEOUL, Aug. 9 (Yonhap) -- North Korea fired some 110 rounds of artillery Monday into its side of a disputed maritime border with South Korea, South Korean military officials said.

   The North Korean move comes right after South Korea ended five-day navy massive naval exercises near the Yellow Sea border in a show of force against its communist neighbor that it blamed on sinking one of its warships in March that killed 46 sailors.

   North Korea had warned of "strong physical retaliations" against the drills which it denounced as preparations for a northward invasion.

   North Korea first fired some 10 shells over three minutes starting at around 5:30 p.m., said at official at the South's Joint Chiefs of Staff. It then fired about 100 rounds between 5:52 p.m. and 6:14 p.m., he said.

   The rounds all landed into the North Korean side of the so-called Northern Limit Line (NLL) that has served as a de factor border in the Yellow Sea, the official said.

   "The Navy heightened its readiness posture" in the wake of the artillery firing, said the JCS official, adding there has been no North Korean firing afterwards.

   The NLL was drawn by the United Nations at the end of the 1950-53 Korean War. North Korea has never recognized it, making it a constant source of military tension between the two Koreas.

   The area is the scene of bloody gunbattles between the navies of the two Koreas in 1999, 2002 and most recently in November last year.

   South and North Korea are still technically at war, with no peace treaty signed at the end of the 1950-53 Korean War. About 28,500 U.S. troops are stationed in South Korea as a deterrent against the North.

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