Defense Department officials reported that the Chinese military is launching cyberattacks on the United States, a charge the Chinese government has denied.

“[I]n 2012, numerous computer systems around the world, including those owned by the United States government, continued to be targeted for intrusions, some of which appear to be attributable directly to [Chinese] government and military organizations,” David F. Helvey, deputy assistant secretary of defense for East Asia, told reporters during a briefing on a new report on Chinese military capabilities.

The Chinese government denied that it was launching such attacks earlier this year. ”The Chinese military has never supported any kinds of hacker activities, so saying that the Chinese military is involved in Internet attacks is neither professional nor consistent with the facts,” the country’s Ministry of National Defense said after Mandiant, a cybersecurity firm, released a report on China’s cyberwarfare in February.

Helvey’s comments on Monday are a more overt accusation than the one he made last year. “I think we have concerns about a number of computer network operations and activities that appear to originate from China that affect DOD networks,” Helvey said last May, without specifically attributing the attacks to the Chinese military.