Ukrainian officials claimed Tuesday that a series of cyberattacks took down the military's, defense ministry's, and key banks' websites, as emotions over the danger of a Russian invasion remained high.
According to several Ukrainian government organizations, the breach affected the websites of the Ukrainian Defense Ministry and Armed Services, as well as Oschadbank and Privatbank, two of the country's largest lenders.
Websites are overrun by a deluge of garbage data packets during such attacks, leaving them inaccessible.
Kyiv has blamed Moscow for similar activities in the past and since Russia began massing more than 100,000 troops near the border, escalating East-West tensions in the face of Western suspicions that Russia is plotting an invasion on Ukraine, which Moscow denies.
"There is no threat to depositors' funds," the Ukrainian Information Ministry's Center for Strategic Communications and Information Security, said.
The accusations rapidly sparked alarm, especially given the U.S. government's ongoing warnings that Russia may execute a huge cyberattack against Ukraine's essential infrastructure, such as communications or banking, prior to an invasion.
U.S. President Joe Biden cautioned that he would work with allies to address the cyber intrusions and that a Russian attack remained a possibility.
East-West ties are in the midst of one of their most serious crises in decades, owing to disagreements over Ukraine, post-Cold War dominance on the continent, and energy supply.
According to U.S. intelligence assessments, Europe and the United States want Moscow to reverse its force buildup near the Ukrainian border. They have proposed defusing the impasse through armaments control and confidence-building measures.
The Ukrainian military ministry's website was down for maintenance, according to a statement on the home page. The ministry tweeted that its website had reportedly been hacked and that it was attempting to restore access.
Meanwhile, Cloudflare, a well-known supplier of denial-of-service security located in San Francisco, claimed it has seen no evidence of "significant DDoS activity" against its data centers or customers in Ukraine.
The U.S. and its partners have signaled their readiness to retaliate to Russian cyberattacks, even if details remain scarce.
Jen Psaki, the White House press secretary, said there were a variety of ways "we might respond - both visible and invisible - to a cyber attack or any other strike."
Since 2014, when Russia invaded the Crimean Peninsula and backed separatists in eastern Ukraine, the latter has been subjected to a constant barrage of Russian cyber assault.
