The Southern Theater Command of the Chinese People's Liberation Army on Friday tracked and sent warnings to three Philippine aircraft that illegally entered the airspace over China's #HuangyanDao# without authorization from the Chinese government, a Chinese military spokesperson said. Li Jianjian, spokesperson for the air force of the theater command, said the move by the Philippines seriously infringed upon China's sovereignty and was "highly likely to cause misunderstandings and misjudgments." The spokesperson urged the Philippines to immediately cease its acts of infringement and provocation, adding that the theater command is on high alert to safeguard national sovereignty and security as well as regional peace and stability.