The cache contains documents generated by the NSA and other agencies and includes names of U.S. and allied intelligence personnel, seven current and former U.S. officials and other sources briefed on the matter said.

 

The data is protected with sophisticated encryption, and multiple passwords are needed to open it, said two of the sources, who like the others spoke on condition of anonymity to discuss intelligence matters.

 

The passwords are in the possession of at least three different people and are valid for only a brief time window each day, they said. The identities of persons who might have the passwords are unknown.