WASHINGTON • The two Russian intelligence agents the US authorities say directed the scheme to hack into millions of Yahoo e-mail accounts, Dmitry Aleksandrovich Dokuchaev and Igor Anatolyevich Sushchin, worked for an arm of Russia's Federal Security Service (FSB) that is supposed to help foreign intelligence agencies catch cyber criminals.
Instead, they helped the hackers avoid detection. Russian government officials were among their victims - including an officer with the Russian Internal Affairs Ministry's cybercrime unit - suggesting that the FSB was using its own intelligence resources to gain an advantage over a rival agency.
Officials provided little information about Sushchin, 43, an FSB supervisor who the indictment says was embedded as a cyber-security expert in a Russian financial firm.
But there is plenty of intrigue swirling about Dokuchaev, 33, who the indictment describes as wanted cyber criminal Alexsey Belan's direct FSB contact. He is also said to have been in contact with Karim Baratov, another hacker indicted by the US authorities.
In Russia, Dokuchaev was arrested on suspicion of treason in early December and accused of passing secret information to the US. He may face as many as 20 years in prison if convicted on treason charges. The authorities have offered no public details of the charges, in what is one of the highest- profile counter-intelligence detentions in the post-Soviet period.
After the arrests, respected Moscow newspaper RBC described him as a former hacker using the online pseudonym "Forb" - who agreed to work for the FSB to avoid prosecution for credit-card fraud.
In an interview with Vedomosti newspaper in 2004, a hacker identified as Forb bragged about hacking a "US government website", calling it his "crowning achievement".
US officials said on Wednesday they were not certain if the Dokuchaev arrested in December was the same man as the one in the indictment.