Reporter Glenn Greenwald, who broke the story about National Security Agency leaker Edward Snowden’s disclosure of classified surveillance programs, said the former contractor held additional documents, including “blueprints” detailing the spy agency’s operations.

“In order to take documents with him that proved that what he was saying was true, he had to take ones that included very sensitive, detailed blueprints of how the NSA does what they do,” said Greenwald in an interview with The Associated Press published Sunday. 


Greenwald said Snowden had “literally thousands of documents,” which he called “basically the instruction manual for how the NSA is built.”

The Guardian reporter said Snowden did not want to reveal the information because it would allow others to duplicate the NSA’s surveillance programs.

Greenwald’s latest comments come days after he warned that Snowden would release damaging information if he was not granted safe passage to asylum in a third country or if harm came to him.

“Snowden has enough information to cause more damage to the U.S. government in a minute alone than anyone else has ever had in the history of the United States,” Greenwald told an Argentine newspaper last week.

“The U.S. government should be on your knees every day praying that nothing happens to Snowden because if something happens, all information will be revealed and that would be their worst nightmare,” he added.

Snowden, who is facing espionage charges, is seeking to avoid a U.S. extradition order. He is in Moscow airport’s transit area as he finds a way to reach Latin America, where three countries – Venezuela, Bolivia and Nicaragua – have offered him political asylum.

Friday, in his first public appearance in weeks, Snowden met with human rights groups at the airport and said he would seek temporary asylum from Russia to allow him to leave the airport transit area and travel to a third country. Russian officials said they have yet to receive a request from him.

The U.S. is pressuring nations not to grant Snowden refuge and officials said President Obama is personally appealing to Russian President Vladimir Putin to help return the fugitive.

Greenwald told the AP that Snowden was “concerned” about his safety. 

The reporter again vowed to share further classified documents taken by Snowden if any harm should come to the NSA leaker.

“It's not just a matter of, if he dies, things get released. It's more nuanced than that,” Greenwald said. “It's really just a way to protect himself against extremely rogue behavior on the part of the United States, by which I mean violent actions toward him, designed to end his life, and it's just a way to ensure that nobody feels incentivized to do that.”