The U.S. Department of Homeland Security is looking into hiring contractors to conduct social media monitoring to weed out threats of violence, The Wall Street Journal reports. The proposed work would involve examining internet traffic flows to help identify potential leads on developing attacks. U.S. government officials are reportedly divided on the plan, given how the potential expansion of social media data collection could impede civil liberties. One official said the expanded work is hard to justify because "the definition of what is public (information) is not necessarily settled."