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The US and South Korea hit back at North Korea's claimed successful missile test by firing their own on Wednesday.
China’s Foreign Minister Wang Yi gave a stark warning. "Are the two sides really ready for a head-on collision?"
Seoul's warning came after the North notified UN agencies late on Tuesday of its plan to launch what it called an "earth observation satellite" sometime between February 8 and 25, which follows its purported hydrogen-bomb test last month.