Article Photos: Oklahoma tornadoes: OU's Merv Johnson 'was extremely lucky, but I wasn't very smart' with weather decisions 92/505

Franklin Graham, second from left, leads a prayer after workers installed crosses on Friday, May 24, 2013, outside of Plaza Towers Elementary for the seven victims killed at the school during the May 20 tornado in Moore, Okla. Photo by Aliki Dyer, The Oklahoman