The U.S. National Security Agency, or NSA, has been hacking thousands of computer networks around the world for years, including those belonging to China and Hong Kong, NSA surveillance program leaker Edward Snowden told the South China Morning Post on Wednesday.

Snowden said he believed the NSA had breached as many as 61,000 global targets, of which hundreds were in China and Hong Kong.

“We hack network backbones -- like huge internet routers, basically -- that give us access to the communications of hundreds of thousands of computers without having to hack every single one,” he told the newspaper.

Snowden said his revelations were to lay open “the hypocrisy of the U.S. government when it claims that it does not target civilian infrastructure, unlike its adversaries.”

“Not only does it do so, but it is so afraid of this being known that it is willing to use any means, such as diplomatic intimidation, to prevent this information from becoming public.”

The newspaper said, at Snowden’s request, it cannot reveal details about how it carried out the exclusive interview from a secret location in Hong Kong.

The 29-year-old former employee of Booz Allen Hamilton, an NSA defense contractor, said he would remain in the city until he is “asked to leave,” because he had “faith in HK’s rule of law.”

The Post said Snowden presented documents to support his claim that NSA had been hacking Chinese and Hong Kong networks since 2009, but added that it was unable to verify their authenticity. None of the documents in question dealt with Chinese military systems, according to Snowden.

Snowden claimed NSA's targets included the Chinese University of Hong Kong and “public officials, businesses and students in the city,” and added that his documents also reveal NSA activity against targets in mainland China.

A spokesman for the U.S. consulate in Hong Kong offered no comment on Snowden’s claims, according to the Daily Telegraph.

The Post published an editorial on Thursday demanding “an explanation” from the U.S. government about the NSA's surveillance activity against overseas targets, remarking that U.S. officials had vilified the Chinese government for alleged state-supported cyber attacks on American targets.

The editorial said the “explosive revelations” have “knocked the wind out of Washington’s case against China,” adding: “It looks like a case of the pot calling the kettle black, except the pot is a lot darker in this case.”

The editorial said the NSA defended its surveillance programs in the name of national security, while China’s hacking activities mostly involve commercial and military targets as well as intellectual property theft. However, it also observed that whether the NSA’s program is “more defensible than China’s state-sponsored hacking activities is highly debatable.”

U.S. State Department spokeswoman Jen Psaki, when asked about Snowden’s latest claims during a news briefing on Wednesday, said: “I haven’t seen those specific reports, I can’t speak to them, but there is a difference between going after economic data and financial information that is part of [Chinese] cyber-attacks,” and “going after people who mean to do harm.”

A poll on the Post's website showed that more than 80 percent of its readers believe Hong Kong will not extradite Snowden.