Major-general Eichelsheim said the government had taken the unusual step of releasing details of the operation after United States officials published charges against a number of Russian intelligence agents on Thursday.
It cites attacks on the World Anti-Doping Agency, Ukrainian transport systems, the 2016 U.S. presidential race and others as very likely the work of the GRU.
Now, the USA government is seeking to apply the law to the cyber spies.
"We are going to actually make it clear that where Russian Federation acts, we are going to be exposing that action", Williamson said.
Mr Hampton said "these malicious cyber activities serve no legitimate national security interest".
Dutch and British officials laid out the charges against the GRU on Thursday, listing the group's attempts to steal information, disrupt or otherwise influence a number of high-profile targets, from the Democratic National Committee to the World Anti-Doping Agency.
WADA suspended RUSADA in 2016 and banned Russian athletes from competing in the Rio Olympics that year after finding them to be non-compliant with the body's doping code, in the wake of the McLaren report into Russian state-sponsored doping.
The Labour leader sparked fury after he took months to admit Russian Federation was behind the attack despite British intelligence saying all the evidence pointed to Moscow. American prosecutors have accused 12 suspected Russian spies of hacking Democrat and Hillary Clinton campaign officials. According to United States officials, the Russians also targeted a nuclear power company based in Pittsburgh, Pennsylvania, that supplied nuclear fuel to Ukraine.
"Russia must stop its reckless pattern of behaviour, including the use of force against its neighbours, attempted interference in election processes, and widespread disinformation campaigns".
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Fancy Bear is a nickname for a GRU hacking group. Officials said the men were expelled from the country following the alleged cyber attack.
Welling said that the GRU agents wanted to "intentionally damage world organizations and athletes committed to fairness" by flooding public and social media outlets with the medical records of worldwide athletes and portraying those athletes who actually complied with global anti-doping regulations as cheaters and dopers. Between 2016 and 2018 they also exchanged emails and private messages with some 186 reporters "in an apparent attempt to amplify the exposure and effect of their message", the Justice Department said in a news release.
Four of those charged belong to GRU Unit 26165, which was the other team implicated in the July indictment.
The men were named as Alexei Moronets, Evgeni Serebriakov, Oleg Sotnikov and Alexei Minin.
Dutch investigators said the snoopers nabbed outside the OPCW also appear to have logged into the Wi-Fi networks near the World Anti-Doping Agency and the Malaysian hotels where crash investigators had gathered.
British Prime Minister Theresa May has said GRU officers were behind an attempt to kill former Russian double agent Sergei Skripal and his daughter with a nerve agent in the English city of Salisbury in March.
"The Russian military, and their intelligence arm "the GRU", is responsible for this pattern of malicious cyber activity", the government said in a statement. The Russians left behind their rental auto.
Maria Zakharova, a spokesperson for the Russian Ministry of Foreign Affairs, told a news briefing that the accusations were the product of someone with a "rich imagination". That attack left four people fighting for their lives and one woman dead.
The same level of confidence is attached to a "hack against email accounts belonging to a small (unnamed) UK-based TV station". And it said Russia was behind the October 2017 BadRabbit ransomware attack that rendered computer systems inoperable in Ukraine and at the Russian central bank.