SEOUL, South Korea (CNN) -- North Korea fired several short-range missiles toward the Sea of Japan on Saturday, an act that the U.S. watched closely and South Korea called provocative. N. Korean army soldiers, back, look at a S. Korean soldier, center, in the demilitarized zone in June. Pyongyang fired six short-range missiles in less than seven hours, South Korea's Foreign Ministry said. The missiles were apparently Scud-type, estimated to have a range of about 500 kilometers (310 miles), according to South Korea's Yonhap news agency. South Korean intelligence estimates that North Korea has about 700 such missiles in its arsenal.
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North Korea five Scud-type missiles Saturday that can reach 400 to 500 km
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South Korea has called the launches "a provocative act"
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U.S. diplomat: "This type of North Korea behavior is not helpful"
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Pyongyang test-fired four such missiles off the east coast Thursday
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@placeholder conducted a nuclear test in May, fired test rockets and threatened U.S. and South Korean ships near its territorial waters.
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"The United States is aware of possible missile launches by @placeholder.