Google is warning account holders it believes are targets of state-sponsored attacks.
Affected accounts would have a forboding banner message splashed across Google web sites.
However how it determined that hackers were state-sponsored was privy only to Google: Disclosing such information including its “detailed analysis” and victim reports would assist “bad actors”, it said.
Google has been quick to finger Chinese state-sponsored hackers for previous attacks. It blamed such hackers for launching the 2010 Operation Aurora attacks against it and a string of high profile companies including Adobe and Juniper Networks.
And in June last year the company claimed to have stopped a sophisticated attack from Chinese actors that targeted human rights activists, government officials and journalists.