Rep. Mike Rogers (R-Mich.) (Al Goldis — Associated Press)

Rep. Mike Rogers (R-Mich.) noted that it might seem odd that a lawmaker charged with overseeing the U.S. intelligence community should lament spying by another government. But he said that China’s espionage activities now extend beyond the U.S. government and military to include scores of private American companies.

“Beijing is waging a massive trade war on us all, and we should band together to pressure them to stop,” he said at a hearing on cyber threats and national security. “Combined, the United States and our allies in Europe and Asia have significant diplomatic and economic leverage over China, and we should use this to our advantage to put an end to this scourge.”

The Chinese government has vociferously denied accusations that it has engaged in a cyber campaign to steal intellectual property.

But security experts have long said that the Chinese government exploits security flaws to sneak into the networks of major financial, defense and technology companies and research institutions in the United States. Lawmakers, too, have raised concern.

Still, Rogers’s remarks represented an unusually frank assessment of the threat from China, and a challenge to the government in Beijing.

The congressman said that although some companies, most notably Google, have come forward to allege they had suffered attacks originating in China, others have stayed silent for fear of provoking further attacks.

“When you talk to these companies behind closed doors ... they describe attacks that originate in China, and have a level of sophistication and are clearly supported by a level of resources that can only be a nation-state entity,” Rogers said.

Michael Hayden, a former director of the CIA and NSA, said at Tuesday’s hearing that the scope of China’s efforts to spy against the United States was stunning.

“I say that as a professional intelligence officer, I step back in awe at the breath, depth, sophistication and persistence of the Chinese espionage effort against the United States of America,” he said.