The launches come as the reclusive communist state has signalled to the outside world that it might return to talks on ending its nuclear arms programme and made overtures to the South for working-level dialogue amid chilled ties.
Indications of the additional launches are coming from the western part of the Korean peninsula, Yonhap quoted the source as saying. North Korea has issued a warning for vessels to stay out of waters off its coasts, Japan's coast guard and Yonhap said.
"There have been indications that the North is getting ready to fire short-range missiles from the west coast," the source was quoted as saying.
North Korea accepted the South's proposal for talks on preventing flooding from a river that flows across their borders after a surge of water last month killed civilians in the South, the South's Unification Ministry said Tuseday.
It also agreed to hold Red Cross talks on arranging reunions for families separated by the 1950-1953 Korean War, the ministry said.
Analysts have downplayed the security threat from the North's missile launches, saying they may be an attempt to gain the upper hand in upcoming talks.
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