In 2014, a group of hackers made off with the account information for 500 million Yahoo users, gaining access to their e-mails and other Yahoo applications.  At the time, it was the largest disclosed data breach in history.  On Wednesday, the Justice Department is moving to indict those responsible, including two criminal hackers, and two Russian operatives.

This marks the first time Russian government officials have been charged with such a crime.

Charges being levied against the four, whose identities have not yet been officially revealed, include hacking, wire fraud, trade secret theft, and economic espionage.  According to sources that have asked to remain anonymous, these charges are a part of the largest hacking case ever brought about in the United States.

According to sources, the FSB, or Russia’s Federal Security Service (the successor to the infamous KGB), sought the information from Yahoo’s servers for intelligence purposes.  Their efforts targeted journalists, political dissidents and U.S. government officials.  They then permitted the other hackers to use the email cache for financial purposes like identity theft, spam, and phishing schemes.

Unconfirmed reports indicate that the Russians being indicted are Dmitry Dokuchaev and his superior, Igor Sushchin.  Each of the men work for the Cyber investigative arm of the FSB, which is similar in mission to the FBI’s cyber division that is traditionally tasked with combating such crimes domestically.

According to the reports, Dokuchaev used the alias “Forb” online, and was one of the men arrested in Moscow last December on charges of treason for passing information along to the CIA.  At the time, it was theorized that the treason charges may have been tied to recent revelations regarding Russian hacking efforts during the 2016 presidential election, with many assuming Dokuchaev was the source of the American intelligence community’s information.

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Alexsey Belan, one of the civilians named by sources, is on the list of America’s most-wanted cyber criminals and has had charges levied against him twice before.  Previous cases involved cyber intrusions into three major tech firms in Nevada and California in 2012 and 2013.  Defense officials said that he had been held in custody in Greece recently, but has since fled to Russia where he is “being protected by authorities.”

The other civilian to be charged is Karim Baratov, a Canadian citizen who was born in Kazakhstan.  He was taken into custody by Canadian officials on Tuesday.

America has no extradition agreement with Russia, so it seems unlikely that the remaining three will be brought into U.S. custody any time soon, particularly as the hacking likely could have been a state-sponsored endeavor.  Despite that, officials claim that bringing up the charges is an important statement to make to the international community.

“They have the effect of galvanizing other countries that are watching what’s happening,” said former deputy assistant attorney general for national security, Luke Dembosky. “They show that we have the resources and capabilities to identify the people at the keyboard, even in the most sophisticated cases.”

There is no word yet as to whether or not these charges are linked to a similar Yahoo breach the year prior, which was eventually revealed to be even larger than the 500 million accounts accessed in 2014.  Any ties between these charges and the Russian hacking of the Democratic National Committee’s e-mail server have not been announced as of yet.

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