After attacking Ukrainian government websites and banks with massive cyberattacks, Russia-sponsored hackers were now hitting Internet infrastructure in the country to silence the locals amid a full-blown war.
The cyber invasion had already cut Internet connectivity in some parts of the country, the reports said on Friday.
"#Ukraine: Partial outage of Ukrainian ISP Triolan started around 2.50 am UTC," tweeted the Internet Outage Detection and Analysis (IODA) project at Georgia Tech in the US late on Thursday.
Outages also affected the Triolan Internet service provider, which services a number of cities and other areas across Ukraine, including Kharkiv, The Verge reported.
"Significant Internet disruption registered in #Ukraine-controlled city of #Kharkiv shortly after huge explosions heard; users report loss of fixed-line service on provider Triolan while cellphones continue to work," tweeted global internet monitor platform NetBlocks.
In an update, NetBlocks said, "A significant internet disruption has been registered in the strategic port city of #Mariupol, Donetsk. The incident comes amid reports of civilian casualties and the loss of telecoms services for many".
Several civil society groups were concerned about the possibility of direct attacks on the country's internet infrastructure.
Russia has previously been linked to DDoS attacks against Ukrainian government sites but a full blackout would mean disabling telecommunications infrastructure at the network level and silencing Ukrainians in the process.
Earlier, as Russia began military operations against Ukraine, key Ukrainian government websites were down as multiple cyberattacks hit the country.
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The websites of the Ukrainian Cabinet of Ministers, and those of the ministries of foreign affairs, infrastructure, education and others, were down.
The US officials had warned that Russia will very likely use cyber operations in conjunction with military action in Ukraine.
Russian President Vladimir Putin launched a full-scale invasion of Ukraine on Thursday. Russian airstrikes hit facilities across the country, triggering condemnation from the West amid warnings of more tough sanctions.
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