The FBI San Francisco office has been has been looking into this case for two years.
It seems the hackers were targeting certain individuals.
The FBI says this was a cyber breach directed by Russian intelligence agencies using cyber mercenary and they say the indictment is unprecedented.
FBI SF says four people including 2 Russian intel officers were indicted i. massive hack of 2015 Yahoo Data base. One arrested in Canada. pic.twitter.com/TFXcuphtj8— Vic Lee (@vicleeabc7) March 15, 2017
The indictment charges that two members of the FSB, Dmitry Dokuchaev, Igor Sushchin, hired criminal hackers, Alexsay Belan and Karim Baratov, to break into Yahoo's database. "It is the first time the FBI has indicted Russian FSB officers for committing criminal cyber intrusions," FBI Special Agent in Charge of San Francisco Office John Bennett said.
RELATED: Russian agents facing charges in massive Yahoo hacks
The FSB, Russia's federal security service, which replaced the notorious KGB, an arm of its military - an intelligence gathering agency.
It says they stole information on more than 500 million Yahoo user accounts in a massive hacking attack in 2014.
RELATED: Yahoo confirms huge data breach affecting $500 million accounts
The FBI says they were able to do that in part by spear phishing, sending fraudulent emails to extract data from users. "Gift cards, credit cards, trying to reset user accounts and all that stuff that goes along with it," Bennett said.
The indictment says they accessed accounts of Russian journalists and politicians critical of the Russian government as well as US government officials and even White House personnel.
Baratov was arrested in Canada Tuesday and the FBI says the other three are in Russia.
It'll be hard getting them. "We do not have an extradition treaty with Russia. We would hope they respect our criminal justice system, and respect these charges and what they need to do," Head of National Security at the U.S. Justice Department Mary McCord said.
"The FBI has a long reach and a longer memory," Bennett said.
Put another way, the world's getting smaller and the FBI's reach longer.
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