(NEW YORK) -- New documents revealed by alleged National Security Agency (NSA) leaker Edward Snowden reportedly show how British cyber spies regularly stole secrets from foreign diplomats during the 2009 G20 summit in London.
During an espionage campaign, which was reported Sunday by the U.K.'s The Guardian newspaper, England's Government Communications Headquarters (GCHQ) allegedly set up Internet cafes outfitted with email interception and key-logging software designed to track any delegates' computer use there. The GCHQ also allegedly hacked into delegates' BlackBerry phones to read their emails and gather phone call information.
The documents also reportedly show that the GCHQ's sister organization in the U.S., the NSA, tried to eavesdrop on Russian leader Dmitry Medvedev as he telephoned back to Moscow via satellite.
One slide that appears to be from a "Top Secret" GCHQ presentation said, "Diplomatic targets from all nations have an MO [modus operandi] of using smart phones... Exploited this use at the G20 meetings last year."
According to The Guardian, another slide describes a method of email interception that can allow the spies to read people's email "before/as they do."
As The Guardian noted, the sophisticated espionage techniques appear "to have been organized for the more mundane purposes of securing an advantage in meetings." One slide brags about "recent successes" including the ability to deliver "messages to analysts during the G20 in near real-time... [and] provide timely information to U.K. ministers."
The revelation on the G20 came just hours before the United Kingdom began the smaller G8 summit on Monday. England's Prime Minister, David Cameron, and President Obama both spoke before reporters Monday at the G8 but did not address The Guardian's allegations or Edward Snowden.
Snowden, who first appeared publicly a week ago to claim he was the source of a series of startling articles on NSA spying that appeared in The Guardian and in The Washington Post, remains in hiding in Hong Kong, where on Monday, The Guardian said he will be answering questions from readers.
Top U.S. administration officials acknowledged and defended the previous surveillance programs revealed by Snowden. Late last week, U.S. officials told ABC News they feared Snowden could defect to China with a head, and several computers, full of secrets. The Chinese foreign ministry reportedly denied that Snowden was their spy on Monday.
A spokesperson for the GCHQ told ABC News of Sunday's report from The Guardian, "We do not comment on intelligence matters."
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