A United States aircraft carrier group entered the South China Sea, the military said Sunday. The strike group is formally "conducting routine operations, promoting freedom of the seas, and reassuring allies and partners," Rear Adm. Doug Verissimo said. The ships entered the area the same day that China launched an incursion into Taiwanese airspace Saturday that was more aggressive than usual, in terms of both the amount and type of military aircraft that entered the zone. China considers Taiwan its territory and its sovereignty remains a crucial global issue. The U.S. does not officially recognize Taiwan, but is a key ally, and the sides continue to strengthen ties as Washington's relationship with Beijing deteriorates.

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