The government transparency website Cryptome.org has published 1,350 names and email addresses of corporate titans, media figures and policy executives who are on the Council on Foreign Relations.
The list includes hundreds of intelligence, defense, government and corporate heavyweights who are members of the New York-based group.
All are contained in a 76-page contact list of CFR members interested in intelligence issues.
The Council on Foreign Relations responded to reports of the hacking by noting that the hack itself was not of the organization's computer network but of an individual email account that contained the list.
A CFR spokesperson clarified earlier reports by noting the list contained 1,350 names, not 1,500 as sources initially said. CFR also noted that the list contained email addresses, cities of residence and zip codes, but not exact addresses of its members.
The council publishes a list of its members on its website, but does not include email or location information.
This is the latest leak from a hacker known as "Guccifer" and published on Cryptome, an established government transparency site. Guccifer is best known for hacking the email account of a Bush family member and releasing images of paintings done by President George W. Bush in the years since his time in office.
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