There is no way hackers -- including those from China -- can access top-secret data by penetrating the firewalls of military or government networks, an acclaimed Internet scientist said on Wednesday.

Professor Fang Binxing, former director of the national computer network emergency response team, said there is no scientific basis to blame either China's military or the government for hacking other nations' networks because most of them are "out of reach".

The foreign media, quoting insiders in overseas intelligence services, have recently claimed that hackers, who appeared to be based in China, had repeatedly infiltrated military networks and government computers in more than 100 countries.

"Networks containing sensitive intelligence are impenetrable, because normally the militaries isolate their networks completely from the public domain to prevent hacking," said the specialist on Internet security who is also an academician with the Chinese Academy of Engineering.

"If there have been cases of key intelligence being stolen, I believe there would have been undercover agents within the organizations facilitating the theft you cannot simply do it with computer technology," he added.

Fang Xingdong, a Beijing-based Internet technology expert, said China has become a staging post for hackers worldwide, who use the country's network security vulnerability to launch attacks on other countries.

"Hackers often use computers based in China as their 'springboard'. That makes it confusing even for the US military," he told China Daily.

According to an Internet security report released on April 15 by Symantec, the California-based anti-virus software maker, about 71 percent of the computers hacked in the Asia-Pacific region are based in China, which has a cyber population of 300 million.

At the same time, 38 percent of hacking attempts worldwide originate in the US, compared with 13 percent in China, the report said.

"The US military is picking on China because it wants to make its claims appear more plausible," Fang Binxing said.

The Wall Street Journal quoted US intelligence sources as saying in late March that hackers based in China had stolen data from the Pentagon's US$300 billion Joint Strike Fighter project, and also infiltrated the US state power grid.

The Journal quoted former US officials as saying the attacks seemed to have originated in China, although it noted it was difficult to be absolutely sure.

Canadian-based researchers have also claimed that a cyber spy network based mainly in China hacked into classified documents from government and private organizations in 103 countries, including the computers of the Dalai Lama and Tibetan exiles.

The researchers also dubbed the alleged infiltration "GhostNet" but "whether it's called 'GhostNet' or something else, it's just an expression, not a technical term in any sense," Fang said.

The academician also rebutted reports by foreign newspapers claiming that China's indigenously-built security operating system "Kylin" has links to military use.

"From the start, 'Kylin' was designed and used for civilian purposes only. In fact, the largest user is China Construction Bank," he said.

(China Daily May 21, 2009)