WASHINGTON — Construction is underway on the South Lawn of the White House as construction crews raise steel arches, lighting rigs and broadcast infrastructure to complete a temporary arena for "UFC Freedom 250." The professional fighting event tied to America's 250th anniversary celebration is scheduled for June 14, which marks Flag Day and President Donald Trump's 80th birthday. The most prominent feature currently taking shape is a star-spangled arch that will stretch over the octagon fight cage, featuring a red, white and blue color scheme and extensive lighting effects. The semicircular structure behind the octagon was manufactured in Pennsylvania and...