Pentagon spokesman Rear Adm John Kirby
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Rear Adm John Kirby: IS fight 'will take years'

Pentagon spokesman Rear Adm John Kirby has said the US-led air strikes on Islamic State (IS) targets in Syria were a success, disrupting and degrading the militant group's ability to command and control its forces.

"We have hit what we were aiming at," he said in an interview with Jane O'Brien on BBC World News America.

"Every indication that we've had so far is that we were very successful."

But Adm Kirby cautioned the campaign against the group would take years.

"We have been very clear-eyed about the challenge in front of us," he said.

He said IS was an "adaptive, smart enemy" that has altered its tactics across the border in Iraq in response to air strikes from the US and ground attacks from Iraqi troops.

"I expect that we'll start to see some changes inside Syria based on last night's events," he said.

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