Workers at two Chicago-area Coca-Cola production plants went on strike Dec. 3, 2015, to protest unfair labor practices including delay tactics and intimidation as they try to hash out a new contract. In letters arriving this week at the homes of striking Coca-Cola employees, the company alleges union leaders are engaged in "false attacks" and says it has asked the National Labor Relations Board for an expedited investigation into allegations of unfair labor practices, confident of its actions during negotiations.