Armed drones. Mass graves. Kirkuk's effective annexation. The Iraq crisis escalated Friday. A U.S. official confirmed to CNN that armed American drones started flying over Baghdad in the previous 24 hours to provide additional protection for 180 U.S. military advisers in the area. Until now, U.S. officials had said all drone reconnaissance flights over Iraq were unarmed. Using the drones for any offensive strikes against insurgent Islamic State in Iraq and Syria fighters would continue to require approval from U.S. President Barack Obama. Also on Friday, Kurdish leader Masoud Barzani said disputed areas in northern Iraq, including the oil-rich city of Kirkuk, are part of the Kurdish autonomous region from now on after the Iraqi central government failed to hold a long-awaited referendum.
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Kurdish leader  Barzani effectively annexes Kirkuk
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Armed U.S. drones are protecting 180 American military advisers, source says
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Iraqi Prime Minister: We're buying fighter jets from Russia and Belarus
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Human Rights Watch says graves are thought to hold slain Iraqi soldiers, police and civilians
The move could complicate efforts by the United States and its allies to get Iraqi leaders to form a new government representing all three major population groups -- Sunnis, Shias and @placeholder.