"The blast happened shortly after 7:30 p.m. on the South Oval, across the street from the Gaylord Family-Oklahoma Memorial Stadium, where more than 80,000 people were watching the OU-Kansas State football game. One person who responded to the scene said she heard the blast from four miles away."
Link: http://www.normantranscript.com/homepage/local_story_275013811.html?keyword=leadpicturestory