China issued a denial that it is responsible for the cyber attacks launched against some US government agencies and businesses. On Monday, the US Defense Department published a report directly linking the China government to incidents of cyber espionage.

It was the first time that the US government categorically accused China's military as being guilty of underground operations. The Pentagon further reported that these cyber attacks on US defense systems were used by China's People's Liberation Army to detect weaknesses that could be abused in times of crisis.

Hua Chunying, Foreign Ministry spokesman of China, has strongly denounced the report and said that such allegation is not helping US-China bilateral relations. These accusations, he said, have been brought up year after year and are just being used to justify efforts of the US to boost its military power while hyping China's so-called combative threat.

It was earlier this year when a detailed study by a US computer security company Mandiant was released accusing China's People's Liberation Army Unit of trying to steal confidential information from government agencies and corporations in the US.

According to the Pentagon, stealing industrial technology is the primary goal of China's cyber attacks. It reported China's alleged plan to mobilize several combative aircraft carriers in the next 15 years. Last September, China commissioned its first aircraft carrier, the Liaoning. China is also developing stealth aircraft, the Pentagon added, with the first of its kind tested in 2011.

Meanwhile, Xiaohe Cheng, an International Relations professor at Renmin University, admitted that China is beefing up its cyber research program. But he added that this is just a part of a bigger plan to strengthen China's defense capabilities.

"The Chinese government has tried to build strong mutual forces that offers kinds of security for its marine borders as well as land territory borders," Xiaohe said.

Aside from territorial security, China is also reinforcing its capabilities in two new areas - outerspace and cyberspace - according to Xiaohe.

The US, on the other hand, is investing billions of dollars in shoring up its cyber defense and weapon capabilities. By 2015, about 13 cyber responsive teams would be equipped to deliver offensive responses in case the US is attacked in cyberspace, according to some US authorities.

The Pentagon said China's military expenditure is much higher than the amount China announced in March this year. China reported a 10.4 percent increase to US$114 billion in its annual budget for defense. The Pentagon countered China could have easily spent between US$135 billion to US$215 billion in 2012.