President Barack Obama has nominated a US Navy officer, Vice Admiral Michael Rogers, to take over as head of the embattled National Security Agency, the Pentagon said Thursday.

"This is a critical time for the NSA, and Vice Admiral Rogers would bring extraordinary and unique qualifications to this position as the agency continues its vital mission and implements President Obama's reforms," Defense Secretary Chuck Hagel, who recommended Rogers for the post, said in a statement. If confirmed by lawmakers, Rogers would also take over as head of the military's cyber warfare command.

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