A group of US fighter jets stationed in South Korea joined an annual aerial exercise in Singapore last month, the US Air Force has said, with a commercial aircraft refueling the fighters en route to the city-state for the first time. The US military deployed six F-16s of the 51st Fighter Wing at Osan Air Base in Pyeongtaek, 60 kilometers south of Seoul, to participate in the bilateral Commando Sling exercise with the...