An image grab taken from a propaganda video, uploaded on June 11, 2014 by jihadist group the Islamic State of Iraq and the Levant , allegedly shows ISIL militants gathering at an undisclosed location in Iraq’s Nineveh province U.S. federal authorities cautioned local law enforcement on Friday to be aware that supporters of Islamic State have been calling for their sympathizers to attack holiday gatherings in the United States, including churches, CNN reported. The warning, issued in a bulletin to local law enforcement, said there were no known specific, credible threats, CNN said.