China accused the United States on Thursday of faking facts, after the head of the FBI said that Chinese hacking likely cost the U.S. economy billions of dollars every year.
Charges over hacking and internet spying have increased tension between the two countries. In May, the United States charged five Chinese military officers with hacking into U.S. companies, prompting China to suspend a Sino-U.S. working group on cyber issues. China has denied wrongdoing.
Speaking on CBS' 60 Minutes program on Sunday, FBI Director James Comey said Chinese hackers were targeting big U.S. companies, and that some of them probably did not even know they had been hacked.
Chinese Foreign Ministry spokesman Hong Lei, asked about Comey's remarks at a daily news briefing, said China banned hacking and "firmly strikes" against such criminal activity.
"We express strong dissatisfaction with the United States' unjustified fabrication of facts in an attempt to smear China's name and demand that the U.S.-side cease this type of action," Hong said.
"We also demand that the U.S. side cease its large-scale systematic internet attacks on other countries. The United States tries to divert attention by crying wolf. This won't succeed."
Many in China view the United States as being hypocritical following revelations about its own extensive spying by former U.S. intelligence contractor Edward Snowden.
Comey said Chinese hackers were seeking to obtain all sorts of information, including company negotiation tactics.
"I liken them a bit to a drunk burglar. They're kicking in the front door, knocking over the vase, while they're walking out with your television set. They're just prolific," Comey said.