June 17, 2013  -- New documents revealed by alleged NSA leaker Edward Snowden reportedly show how British cyber spies regularly stole secrets from foreign diplomats during the 2009 G-20 summit in London.

During 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' blackberries 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 National Security Agency (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 G-20 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 G-20 in near real-time... [and] provide timely information to U.K. ministers."

The revelation on the G-20 came just hours before the United Kingdom began the smaller G-8 summit Monday. England's Prime Minister, David Cameron, and President Obama both spoke before reporters today at the G-8 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 today he answered online questions from readers.

Snowden: US Can't 'Cover This Up… By Murdering Me'

The first question fielded today by Snowden came from The Guardian columnist Glenn Greenwald, who published the first of the NSA surveillance stories based on Snowden's information. One thing Greenwald asked was if information would continue to leak if "anything happens" to Snowden.

"All I can say right now is the U.S. government is not going to be able to cover this up by jailing or murdering me," Snowden reportedly wrote back. "Truth is coming, and it cannot be stopped."

TIMELINE: Edward Snowden's Life as We Know It

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 today.

During the online question and answer, Snowden denied that he had given any secret information to, and said he had "no contact" with, the Chinese government.

"This is a predictable smear that I anticipated before going public, as the U.S. media has a knee-jerk 'RED CHINA!' reaction to anything involving HK [Hong Kong] or the PRC [People's Republic of China], and is intended to distract from the issue of U.S. government misconduct," Snowden reportedly wrote. "Ask yourself: If I were a Chinese spy, why wouldn't I have flown directly to Beijing? I could be living in a palace petting a phoenix by now."

Snowden said he "only work[s] with journalists."

Snowden's Father Asks Him to Come Home

Snowden's father, Lonnie, defended his son's integrity in a Fox News report today but pleaded with him to "not release any secrets that could constitute treason."

"I would like to see Ed come home and face this," the elder Snowden said, saying he has faith in the U.S. justice system. "I shared that with the government when I spoke with them. I love my son."

Later, Lonnie Snowden seemed to echo his son's concerns over U.S. surveillance programs.

"I don't want them reading my email… If we say, 'Oh my gosh, we're going to have to… sacrifice our freedoms because of the threat of terrorism,' well, the terrorists have already won because it's our freedoms that make us Americans," he said.

Turkey, Russia React to G-20 Report

The Turkish government said yesterday it asked the U.K. for a "satisfying" answer about the reported surveillance program, which allegedly targeted the Turkish finance minister.

"If a news report claiming that the British government eavesdropped on Finance Minister Mehmet Simsek and his delegation during the G-20 finance ministers' meeting in London in 2009 proves to be true, this would be a scandal which would obviously be unacceptable for Turkey," the Turkish Foreign Ministry said in a statement according to Turkey's Hurriyet Daily.

Though a Russian lawmaker reportedly also referred to The Guardian's assertions as the makings of a "scandal," Viktor Ozerov, chairman of the Russian Federation Council's Defense and Security Committee was quoted in the Russian state press as saying, "There is no need to dramatize the situation."

"Intelligence services exist no just to spy on private individuals, but also on heads of state," he said.

A spokesperson for the GCHQ told ABC News of Sunday's report from The Guardian, "We do not comment on intelligence matters."

READ: The Guardian Report on GCHQ's Alleged Diplomatic Spying

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