Before today's anticipated announcement by the Justice Department, more details are already leaking out about who they're after: "two Russian spies, and two criminal hackers."

The case involves the much-reported 2014 breach of some 500 million Yahoo user accounts. The Washington Post reports that this will be "the first U.S. criminal cyber charges ever against Russian government officials."

Two men who worked for the 'cyber investigations' branch of Russia's FSB intel agency, and two hackers hired by the Russians, are named in the indictments. Charges against them include "hacking, wire fraud, trade secret theft and economic espionage," according to reports citing anonymous U.S. officials. This is the largest hacking case ever brought by the United States.

More on the 4 men indicted:

The indicted FSB officers are Dmitry Dokuchaev and Igor Sushchin, his superior. Particularly galling to U.S. officials is that the men worked for the cyber investigative arm of the FSB — a rough equivalent of the FBI's Cyber Division. That the agency that is supposed to investigate computer intrusions Russia is engaged in hacking is "pretty sad," one official said. Dokuchaev, whose hacker alias was "Forb," was arrested in December in Moscow, according to the news agency Interfax, on charges of state treason for passing information to the CIA. He had reportedly agreed to work for the FSB to avoid prosecution for bank card fraud. Another man indicted in the case is Alexsey Belan, who is on the most-wanted cyber list and has been charged twice before, in connection with intrusions into three major tech firms in Nevada and California in 2012 and 2013. He was in custody in Greece for a time, but made his way back to Russia, where he is being protected by authorities, officials said. The other hacker-for-hire is Karim Baratov, who was born in Kazakhstan but has Canadian citizenship. He was arrested in Canada on Tuesday. The indictments grew out of a nearly two-year investigation by the San Francisco FBI with the aid of international law enforcement, officials said. Sanctions and criminal charges are two tools that the Obama administration began using to punish and deter nation state hackers.

More in Ellen Nakashima's report.