US officials on Wednesday exposed a major alleged Chinese cyber-espionage campaign they say has compromised or attacked numerous federal agencies including NASA, the Federal Reserve, the departments of Justice and Energy and the US Senate.

Hackers affiliated with the Chinese military and intelligence services allegedly used a Chinese tech company to try to cover their tracks, burrow into target networks and make their attacks more efficient. Other targets include US military networks, hospitals, power companies and defense contractors, according to the Justice Department.

The department tried to stop further damage on Wednesday by seizing three internet domains affiliated with the Chinese company. Federal agencies also plan to release an advisory on the hackers’ techniques so victim companies can kick the intruders out.

The full impact of the spying effort was not immediately clear. Any counterintelligence assessments of the damage by US officials are likely to remain private due to security concerns.

The hacking began in 2018 and continued through 2026, according to an affidavit written by an FBI agent in support of the domain seizures. The affidavit lists three unnamed Department of Energy National Laboratories, the National Institutes of Health, and a Department of Health and Human Services agency, among other organizations, as “victims” of the hackers, indicating successful break-ins. The affidavit says the Department of Justice, the Federal Reserve, NASA and the Senate, among other entities, were “targeted” by the hackers.