Federal officials express concern over a pattern of vandalism at the National Mall in Washington, D.C., including the Reflecting Pool liner being cut and threats written in blood. Don’t just watch Fox News—be part of it. Become a Fox News Patriot today. https://youtube.com/foxnews/join Subscribe to Fox News: https://bit.ly/2vBUvAS Watch more Fox News Video: http://video.foxnews.com Watch Fox News Channel Live: http://www.foxnewsgo.com/ Download the Fox News app: https://foxnews.onelink.me/xLDS/