Tsinghua University in Beijing, widely regarded as the mainland’s top education and research institute, was the target of extensive hacking by US spies this year, according to information leaked by Edward Snowden.

It is not known how many times the prestigious university has been attacked by the NSA but details shown to thePostby Snowden reveal that one of the most recent breaches was this January.

The information also showed that the attacks on Tsinghua University were intensive and concerted efforts. In one single day of January, at least 63 computers and servers in Tsinghua University have been hacked by the NSA.

Snowden said the information he shared on the Tsinghua University attacks provided evidence of NSA hacking because the specific details of external and internal internet protocol addresses could only have been obtained by hacking or with physical access to the computers.

The university is home to one of the mainland’s six major backbone networks, the China Education and Research Network (CERNET) from where internet data from millions of Chinese citizens could be mined.

The network was the country’s first internet backbone network and has evolved into the world’s largest national research hub.

It is one of the mainland’s non-commercial networks, owned by the Ministry of Education, but operated and maintained by the university and other colleges.

Universities in Hong Kong and the mainland were revealed as targets of NSA’s cyber-snooping activities last week when Snowden claimed the Chinese University of Hong Kong had been hacked.

Chinese University is home to the Hong Kong Internet Exchange, the city’s central hub for all internet traffic.

Snowden said the NSA was focusing much attention on so-called “network backbones”, through which vast amounts of date passed.

In the wake of Snowden’s claims, the Ministry of Foreign Affairs set up an office to deal with diplomatic activities involving cyber security.

The new cyber affairs office is the first of its kind on the mainland with a Foreign Ministry spokeswoman saying that Beijing, long accused of cyberhacking by the United States, has been a “a major victim” of cyberattacks and that it opposed “cyberattacks in all forms”.

She added that the central government would discuss cybersecurity issues with the United States at next month’s Sino-US strategic and security dialogue.

Professor Xu Ke, deputy director of the Institute of Computer Networks at Tsinghua University, has previously said that most data passing through network backbones was not encrypted.

Xu said most attacks on such networks were carried out by governments because individual hackers “could gain little”, as the amount of information they faced would be “colossal”.

Only governments or large organisations would have the resources and manpower to “find the needle in a haystack”, he said.