US deployed cyber force in Ukraine since fall: NSA Chief

The US Cyber Command has been deploying forces in Ukraine ever since accusing Russia of an "invasion", according to the force's top officer and National Security Agency (NSA) commander, Gen. Paul Nakasone, who testified before Congress on Tuesday.

"Coordinating with the Ukrainians to help them harden their networks, we deployed a hunt team who sat side-by-side with our partners to gain critical insights that have increased homeland defense for both the United States and Ukraine," Nakasone told the US Senate Armed Services Committee.

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"We provided remote analytic support to Ukraine and conducted network defense activities aligned to critical networks from outside Ukraine - directly in support of mission partners. ...We have provided intelligence on the building threat [and] helped to warn US government and industry to tighten security within critical infrastructure sectors," Nakasone said.

He claimed that Russia’s military and intelligence forces were allegedly employing a range of cyber capabilities, including espionage, influence, and attack units to support the Russian operation and to back Russian actions with a worldwide propaganda campaign.