Experts have long suspected China to be the host of cyber attacks on U.S. businesses.

This week Chinas government noted the existence of their cyberwarfare unit in a publication put out by a research institute of the Peoples Liberation Army.

The Chinese government has long denied attacking U.S. targets whilst U.S. businesses and government agencies have complained for years about cyber attacks originating from China.

Most people in the cybersecurity industry didn’t take the news as a shock with most saying it was quite obvious that China had such units in place.

Ken Westin a security analyst at Tripwire said it’s naive to think countries aren’t developing cyberwarfare capabilities, he believes they train “cybermercenaries” focused on economic espionage.

In May last year the United States charged five Chinese nationals who they described as “military hackers” with the intent of stealing sensitive data from US corporate networks. Google also accused the Chinese government in 2010 of sponsoring attacks against it and numerous other technology companies. It is believed the Chinese cyberwarefare units target US companies in order to steal valuable data which can be used for business and trade.

In 2014, James Comey, FBI Director said cyber attacks cost US businesses billions every year with Chinese hackers being “aggressive” and “widespread” in their attempts to break into US systems.

He also said much of the damage is caused mostly by their persistence and no due to their sophistication with him referring to some of them acting like drunk burglars when accessing US networks.

Technology firms believe the U.S. must develop the capability to launch retaliatory and pre-emptive attacks to deter such activity in the future.