China’s foreign ministry has urged New Zealand and US spying agencies to stop hacking into Chinese diplomatic buildings in Auckland. This follows reports exposing the practice and citing secret NSA files, which were leaked by Edward Snowden.

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New Zealand and US intelligence agencies were hacking into a link between the Chinese consulate and their passport office, according to a report by The Herald on Sunday in cooperation with The Intercept, based on the Snowden revelations.

"We are extremely concerned about this report. We strongly urge the relevant countries to immediately stop using the Internet to damage the interests of China and other countries," said Chinese Foreign Ministry spokesman Hong Lei in a statement.

However, the New Zealand Prime Minister John Key was unapologetic and accused Snowden of being a thief and a liar.

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"[Snowden's] a thief and he stole and you've got a bunch of people who've been out there propagating information that's actually been proven to be incorrect," Key said.

He added that every country including China uses their intelligence services to serve their own interests and that not one country disclosed details of what they are up to.

"They don't do it in the United States ... they don't do it in China, they don't do it anywhere else," Key said.

The claims published in the Herald on Sunday and the Intercept allege that New Zealand’s spy agency, the Government Communications Security Bureau (GCHB), violated international treaties, which forbid the interception of diplomatic communications.

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The document leaked by Snowden clearly says they will instigate passive and active surveillance on Chinese government offices in Auckland.

“GCSB has identified an MFA data link between the Chinese Consulate and Chinese Visa Office in Auckland. NSA and GCSB have verbally agreed to move forward with a cooperative passive and active effort on this link. Formal coordination has begun on both sides and GCSB is providing additional technical data on the link to TAO,” the document states.

There is a difference between passive surveillance and active surveillance. The former hoovers up data from phone and internet networks, while the later involves the planting of spyware or bugs into phones or computers.

In the case of the Auckland operation, it looks like active spyware was embedded onto Chinese government computers.

However, it is not known if the operation is ongoing as Snowden’s leaks took place in June 2013.

China has repeatedly been accused by the US government of hacking into American computer networks and was suspected of being linked to a powerful hack on a New Zealand super computer. Beijing has repeatedly denied all the allegations.

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