While trade relations between Washington and Beijing developed throughout the year, at the same time some Chinese hackers violated the National Association of Manufacturers (National Association of Manufacturers - NAM).
NAM hired a company cybersecurity, which concluded that the attack came from China.
The security firm made the assessment based on tools and techniques previously associated with well-known Chinese hacker groups.
Breaking an internal computer network in a powerful industry group Washington shows how China tried to gain an advantage in the trade war between the world's two largest economies.
It is not clear what data has been stolen. NAM hired an external cybersecurity company to find out where the breach took place and to stop the infiltration.
Spokeswoman Erin Streeter said that, given NAM's high profile, "we know we are targeted for cyber attacks, we detected suspicious activity on certain company systems and investigated the matter." He added that their network is now secure.
The incident happened shortly before a round of official negotiations between government officials. USA and China on a possible deal.
The trade talks between the administration Trump and Beijing included protecting intellectual property and opening up Chinese markets to more American products, issues that directly affect NAM members.
NAM has gained significant influence within the Trump administration as the president has pledged the return of construction jobs in the United States from foreign countries, such as China and Mexico, during campaign events.
It is not clear why the hackers are targeting NAM, but national security experts say it is known that Chinese government agencies are trying to steal sensitive corporate secrets and other information.
US Department of Justice has however accused many Chinese hackers of data theft from private US companies.