The Chinese military resumed cyber attacks on different American companies after lull, The Voice of America reported. A U.S. computer security firm had validated the report.

Mandiant revealed that a Chinese army unit has just gained access inside supposedly classified computer systems of over 100 companies. The cyber attack aimed to steal important trade secrets.

The attacks resumed just within days following Chinese officials' agreement with the Secretary of State John Kerry in April. The agreement involved China's openness to discuss cyber security with the United States.

Chief Security Officer Richard Bejtlich said that China has made use of the same hacking equipment it used with its previous attacks in the companies. Mr. Bejtlich said that China had taken advantage of the fact that the computer systems of those companies it previously attacked remained vulnerable as companies were still figuring out ways t protect their system.

Mr. Bejtlich called for U.S. to employ heightened sanctions against China.

China had reportedly denied the accusation, claiming that they were the ones victimized by American cyber hackers.

Shame Campaign

It was to be recalled that a February report by Mandiant had started a shame campaign against China. The report went about exposing China's Unit 61398 to cyber attacks on 141 companies in the U.S.

China promptly released its statement denying the accusation and accused U.S. for sensationalizing their theory which was all based on mere faulty evidences.

Following China's statement, Mandiant saw that the attacks into the computer system had fade away. The hackers' tools were no longer detectable from all systems that the hackers were able to access.

However, after two months of lull in the hacking activities, Mandiant discovered new addresses and different servers hacking into the computer systems of the same companies.

To date, Mandiant said that the hacking activities were now in 60 to 70 per cent as compared to the previous hacking done in February.

What Could Have Done

Jeffrey Carr, CEO of Taia Global and author of Inside Cyber Warfare: Mapping the Cyber Underworld said that the shame campaign launched against China was an extremely weak strategy.

Mr. Carr, in an interview with PCWorld, said that "It's (shame campaign) a terrible idea. You're not going to stop a government from engaging in espionage, so that should just be off the table."

Mr. Carr explained that the U.S. government should have cooperated and collaborated with China to go after the cyber criminals instead of launching a shame campaign against the country. By doing this, China would be able to scour all its borders for all suspicious internet activities aimed outside its territories.

Mr. Carr emphasized that the "The New York Times and Mandiant have collaborated on this theory that Comment Crew is part of the PLA. Mandiant has never established that. It just made the claim that it is."

Chief Research Analyst at IT-Harvest, Richard Stienon, also told PCWorld that the shame campaign will work as a diplomatic tool, noting North Korea as an example. "We've tried to use it to shame North Korea into behaving itself and obviously that hasn't work."

Mr. Steinon said that another way for U.S. to stop the cyber hackers is to make all access to information and computer systems expensive for the hackers. "Right now it's very inexpensive to engage in these cyber-attacks. Mandiant's report slowed them down, forced them to retrench, pull their tools out and reengage. They spent a lot of man hours because of that report. That reaction was expensive for the attackers."