CIA Chief Warns Of Other Attacks By Islamic State

CIA Director John Brennan delivers remarks remarks at the Center for Strategic and International Studies November 16, 2015 in Washington, DC.

WASHINGTON— The director of the CIA warned that Islamic State militants, who claimed responsibility for last week’s horrific attacks in Paris, may have other operations in the works.

John Brennan also said that while it was "inevitable" that the Islamic State will try to carry out similar attacks, "to me it is not inevitable that they are going to succeed."

He spoke November 16 at a security conference hosted by the Center for Strategic and International Studies, a Washington think tank.

Brennan said foiling any potential plots could prove difficult because Europe's intelligence and security agencies are severely stretched trying to keep track of the hundreds of extremists who have returned home from fighting in Syria and Iraq.

U.S. and European intelligence haven’t confirmed the Islamic State’s claims of responsibility for the Paris assault that killed 129 people but Brennan said the attacks -- as well as the October 31 downing of a Russian airliner that killed 224 people over Egypt -- "bear the hallmarks" of the Islamist group.

With reporting from AP and Reuters