The United States' National Security Agency can observe more online communications of Americans than once believed, according to a new report in the Wall Street Journal.
Quoting a number of NSA officials, the Journal says that the agency is able to spy on 75 percent of US internet traffic.
Revelations of the massive surveillance program by the NSA, via documents obtained by the Guardian and Washington Post newspapers from former security contractor Edward Snowden, have sparked global controversy and debate about the reach of US spy agencies.
The latest report also confirms that programs like XKeyscore, which allows NSA analysts to sift through the contents of email and other online communications, could be used domestically as well as abroad.
The Wall Street Journal writes: "At key points along the U.S. Internet infrastructure, the NSA has worked with telecommunications providers to install equipment that copies, scans and filters large amounts of the traffic that passes through."
The paper continued, "The report also explains how the NSA relies on probabilities, algorithms and filtering techniques to sift through the data and find information related to foreign intelligence investigations."
The new findings implicate major US telecommunications companies like AT&T, which had a hand helping the NSA filter and gather information.
The revelations also show that the spy agency can peer into content, not just the metadata, of communications within the US.
"In some cases, [the NSA] retains the written content of emails sent between citizens within the U.S. and also filters domestic phone calls made with Internet technology..." the Journal wrote.
The report also showed that the NSA and FBI worked together to monitor all email and text messages near Salt Lake City for the six month period before and during the 2002 Olympic Games.
In a statement to Fox News after the new allegations, the NSA said:
"NSA's signals intelligence mission is centered on defeating foreign adversaries who aim to harm the country. We defend the United States from such threats while fiercely working to protect the privacy rights of U.S. persons. It's not either/or. It's both."
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