Seoul, South Korea (CNN) -- North Korea is showing signs it could be preparing to carry out a new nuclear test, South Korea's Unification Minister Ryoo Kihl-jae said Monday, according to the semi-official South Korean news agency Yonhap. Ryoo made the comment in response to a South Korean lawmaker who cited unspecified reports suggesting there had been an increase in activity near the site of the North's three previous underground nuclear tests, Yonhap reported. The South Korean government had said Sunday that it believes North Korea may test a missile about April 10, citing as an indicator Pyongyang's push for workers to leave the Kaesong Industrial Complex by then.
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NEW: South Korean official cites indications another test is being planned
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U.S. commander in South Korea also cancels trip to Washington this week
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Seoul says Pyongyang is trying to make headlines as a scare tactic
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Switzerland offers to host a meeting between North and South Korea
New reports of missile movements in North Korea have triggered military counteractions by @placeholder and the United States.