South Korea and the United States have kicked off major combined training involving five fighter wings to strengthen their multi-domain air operation and response capabilities, the South's Air Force said Tuesday.The five-day exercise, which runs through Friday, brings together some 200 aircraft, including the South's F-15K, FA-50 and KF-16 fighters, and the U.S. F-16 and A-10 fighters, the Air Force said.It marks the first time that multiple fighter wings of the allies take part in around-the-clock air drills across the domains of air, land and sea, it added.The training, which continues for 120 consecutive hours, will involve exercises simulating an infiltration by enemy aircraft and those meant to enhance defense counter-air, air-interdiction and airborne alert interdiction capabilities.The Air Force said the ongoing training was organized in association with the Ulchi Freedom Shield, an annual summertime military exercise between South Korea and the U.S. on an 11-day run through Aug. 29.Source: Yonhap News Agency