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Operation was planned and put in motion before Paris terror attacks

Pentagon: This is the first U.S. strike against an ISIS leader in Libya

Washington CNN  — 

The U.S. military on Friday killed the senior ISIS leader in Libya, the Pentagon said.

Abu Nabil, an Iraqi national and longtime al Qaeda operative, was taken out in an airstrike authorized and initiated prior to the terrorist attacks in Paris on Friday night, said Pentagon Press Secretary Peter Cook.

“While not the first U.S. strike against terrorists in Libya, this is the first U.S. strike against an ISIL leader in Libya and it demonstrates we will go after ISIL leaders wherever they operate,” Cook said.

Nabil – also known as Wissam Najm Abd Zayd al Zubaydi – may also have been the terror group spokesman who appeared in a February video showing the execution on a beach by ISIS of Coptic Christians who had been taken prisoner.

Cook said Nabil’s death will degrade ISIS’s ability to recruit new members in Libya, establish bases in the country, and plan external attacks on the United States.

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President Barack Obama said Friday that the U.S. strategy against ISIS has “contained them,” but not yet succeeded in its effort to “decapitate” the group’s leadership.

“I don’t think they’re gaining strength,” Obama told ABC’s George Stephanopoulos on Thursday for an interview that aired Friday morning.

“What is true, from the start our goal has been first to contain and we have contained them,” Obama added. “They have not gained ground in Iraq and in Syria. They’ll come in. They’ll leave. But you don’t see this systemic march by ISIL across the terrain. What we have not yet been able to do is to completely decapitate their command and control structures. We’ve made some progress in trying to reduce the flow of foreign fighters.”

RELATED: Obama: ISIS not growing, but not ‘decapitated’

At the White House, Obama called the attacks in Paris an “outrageous attempt to terrorize innocent civilians” and the President pledged the U.S. government’s assistance to France.

“This is an attack on all of humanity and the universal values we share,” Obama said Friday in a statement delivered in the Briefing Room. “We stand prepared and ready to provide whatever assistance the people of France need to respond.”

Obama added, “This is a heartbreaking situation, and obviously those of us here in the United States know what it’s like and we’ve gone through these kinds of episodes ourselves.”

RELATED: Why did Obama declare ISIS ‘contained’ the day before Paris attacks?

CNN’s Karl de Vries and Tom LoBianco contributed to this report.