Foreign intelligence services are being warned that leaker Edward Snowden has documents detailing secret cooperation with the United States, officials said.
U.S. officials said former National Security Agency contractor Snowden left with tens of thousands of documents, some of which included sensitive material about programs against countries such as Iran, Russia and China, The Washington Post said. Some of the documents refer to operations that involve countries not publicly allied with the United States.
The notifications come as the Obama administration is trying to soothe allies after allegations that the NSA monitored communications of foreign leaders, including German Chancellor Angela Merkel.
"It is certainly a concern, just as much as the U.S. collection [of information on European allies] being put in the news, if not more, because not only does it mean we have the potential of losing collection, but also of harming relationships," a congressional aide said.
The Office of the Director of National Intelligence is tasked with informing the other intelligence services, officials said. ODNI declined the Post's request for comment.
Snowden took the documents from a top-secret network run by the Defense Intelligence Agency and used by intelligence units of the military branches, unnamed sources told the Post.