According to two U.S. officials, Iran conveyed a private message to President Donald Trump through an intermediary during last week’s G7 summit, warning that if the president launched airstrikes, Iran would respond by activating terrorist sleeper cells in the United States. Meanwhile, the Department of Homeland Security has declared a heightened threat environment in the U.S. NBC’s Peter Alexander reports for TODAY. Meanwhile, newly released images show the massive impact on the nuclear site