"What we found really surprising and new here was the use of criminal contract hackers to conduct this unsanctioned cyber operation and really the criminal activity for financial gain. That was really eye-opening and surprising for us," a senior administration official said on Sunday ahead of the announcement. The official said the US was "not ruling out further actions to hold (China) accountable." The governments also formally attributed with "high confidence" the massive hack in March of Microsoft's Exchange email service on criminal hackers supported by the Chinese intelligence service. The official said the US government wanted to assure it had high confidence in its assessment before formally attributing the hack to China.

Source: CNN July 19, 2021 11:05 UTC