The U.S. National Security Agency (NSA) has been collecting raw data on the email and Internet traffic of U.S. citizens and residents for over two years, Britain's Guardian newspaper reported on Thursday. The paper claims that the collection of the raw internet data began shortly after the attacks of September 11, 2001.

Initially the program collected information in which one party was outside the United States or communications between known foreigners, but expanded in 2007, the paper added, citing a top-secret draft report prepared in 2009 by NSA's inspector general. The paper said the data included the addresses to and from which messages were sent along with IP addresses.

The Guardian had previously unveiled NSA's Prism program, which involved NSA being able to search the content of traffic sent through U.S. Internet companies by foreign intelligence subjects.

The collection program was terminated in 2011, the paper added.

NSA has not commented on the report yet.