Microsoft informs its customers that Russian hackers spied on emails

Russian hackers who broke into Microsoft’s systems and spied on staff inboxes earlier this year also stole emails from its customers, the tech giant said on Thursday, around six months after it first disclosed the intrusion.

The disclosure underscores the breadth of the breach as Microsoft faces increasing regulatory scrutiny over the security of its software and systems against foreign threats. An allegedly Chinese hacking group that separately breached Microsoft last year stole thousands of US government emails.