BEIJING，Aug. 16 -- The PLA Eastern Theater Command organized joint combat-readiness security patrol and combat training exercise involving troops of multiple services and arms in waters and airspace around the Taiwan Island on Monday. During the patrol and exercise, pilots flew the fight jets over the Taiwan Straits and filmed down the bird's-eye view of the Penghu Islands. According to the spokesperson for the Eastern Theater Command, this is a solemn deterrent to the United States and the Taiwan authorities, which have repeatedly played political tricks and undermined peace and stability in the Taiwan Straits. The troops of the PLA Eastern Theater Command will take all necessary measures to firmly safeguard China's national sovereignty and the peace and stability in the Taiwan Straits.