A hacking group backed by a “foreign government” stole information from the US Treasury Department and the Commerce Department’s National Telecommunications and Information Administration (NTIA), Reuters reported Sunday, citing people familiar with the matter.

“The United States government is aware of these reports and we are taking all necessary steps to identify and remedy any possible issues related to this situation,” said National Security Council spokesman John Ullyot.

The hack is so serious it led to a National Security Council meeting at the White House on Saturday, said one of the people familiar with the matter.

The hack on NTIA involved the organization’s Microsoft Office 365 platform, according to Reuters.

The Washington Post reported, citing people familiar with the matter, that Russian government hackers are responsible for the breach. The same hackers earlier breached a top cybersecurity firm, said the sources who requested anonymity because of the sensitivity of the matter.

The FBI is investigating the campaign by a hacking group working for the Russian foreign intelligence service, SVR. The group, known among private-sector security firms as APT29 or Cozy Bear, also hacked the State Department and the White House during the Obama administration, according to the report.