Washington (CNN) -- The top U.S. intelligence official said Tuesday that ISIS was likely to attempt direct attacks on the U.S. in the coming year and that the group was infiltrating refugees escaping from Iraq and Syria to move across borders.
James Clapper, the director of National Intelligence, estimated that violent extremists were active in about 40 countries and that there currently exist more terrorist safe havens "than at any time in history."
Testifying on global threats at a Senate Armed Services Committee hearing, Clapper warned that ISIS and its eight branches were the No. 1 terrorist threat, and that it was using the refugee exodus from violence in Iraq and Syria to hide among innocent civilians in order to reach other countries.
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