Senate investigators concluded the federal government had failed to oversee the operation of Chinese state-run telecom companies inside the United States properly for years, a failure that poses a threat to national security.

The Permanent Subcommittee on Investigations, led by Republican chairman Sen. Rob Portman of Ohio and Democratic ranking member Sen. Tom Carper of Delaware, released a 104-page report on Tuesday titled “Threats to U.S. Networks: Oversight of Chinese Government-Owned Carriers,” which details how the federal government “has provided little-to-no oversight of Chinese state-owned telecommunications carriers operating in the United States for nearly twenty years” and how China is targeting U.S. communications the same way it has targeted education, research, and personal data.