South Korea and the United States kicked off their major spring joint Freedom Shield exercise Monday amid speculation that U.S. Forces Korea's (USFK) Patriot missiles have been deployed to the Middle East as regional tensions rise. The 11-day exercise, which runs through March 19, involves about 18,000 personnel and incorporates lessons drawn from recent wars to reflect evolving and realistic threats in its operational scenarios, according to South Korea's Joint Chiefs of Staff. With Seoul and Washington accelerating efforts to transfer wartime operational control to South Korea, this year's drills are also expected to focus on assessing and verifying whether conditions for the transition have been met. The exercise comes amid rising indications that Patriot missile systems operated by USFK have been redeployed to the Middle East, as demand for interceptor missiles and air defense systems has grown following the Feb. 28 U.S.-Israeli strikes on Iran. Several U.S. military transport aircraft have been seen arriving at and departing from a U.S. air base in Pyeongtaek, just south of Seoul, i