A top US official has urged the Chinese government to take “serious steps” to tackle “unprecedented” cyber-crimes from Beijing.

White House National Security Adviser Thomas Donilon said Monday that cyber security was a “growing challenge” to the two countries’ economic relations, following extensive hacking of US companies that is believed to have originated in China, reports Financial Times.

“The international community cannot afford to tolerate such activity from any country,” Donilon said in a speech at the Asia Society in New York.

“US businesses are speaking out about their serious concerns about sophisticated, targeted theft of confidential business information and proprietary technologies through cyber intrusions from China”.

Donilon called on the Chinese government to acknowledge the problem and put an end to cyber-theft.

He also insisted on international norms of behavior in cyberspace.

China has long been suspected of cyber-attacks. In recent months, Chinese hackers have allegedly targeted US media outlets, including the New York Times. A US cyber security firm Mandiant linked cyber-attacks on US businesses to a specific unit of the Chinese military in Shanghai.

Beijing denounced the Mandiant report as “flawed” and claimed it opposes hacking activities and is a victim of cyber attacks itself, BBC reports.