Two Russian spies are among four individuals indicted by the US Department of Justice over a huge theft of Yahoo user accounts.
Reports say the members of the Russian intelligence agency, the FSB conspired with criminal hackers.
Previously, Yahoo said “state-sponsored” hackers were behind the 2014 breach affecting five hundred million accounts. The suspects are also alleged to have targeted Google accounts.
According to reports, hacking was directed at Russian and US government officials, including security, diplomatic and military personnel.
The indictment also alleged that thirty million Yahoo accounts were commandeered without authorisation for use in a spam campaign.
According to reports, One of the alleged hackers has been on of the FBI’s most wanted cyber criminals for more than three years.
FBI executive assistant director Paul Abbate added that the United Kingdom’s MI5 made substantial contributions to the advancement of this investigation. Yahoo was criticised for the delay in informing users about the 2014 breach.
The stolen data included names, email addresses, telephone numbers, dates of birth and encrypted passwords, but not credit card data, according to Yahoo.
Last year, users were advised to change their passwords.