The hacker group Killnet, which originates from Russia, claimed responsibility for some of the attacks. According to hackers, the cyberattack is revenge for banning the transit of sanctioned goods through Lithuania.
According to the Lithuanian Ministry of Defense, the cyberattacks on Monday were partly aimed at Lithuania's secure data network, a communication network for government officials set up to counter war and other crises.
The National Cyber Security Center of Lithuania (NKSC) stated that users of the secure national data network partially do not have access to the services and work is underway to restore its normal functioning.
"There is a high probability that such, or even more, intense attacks will continue in the coming days, especially against the communications, energy and finance sectors," said NKSC acting director Jonas Skardinskas.
The type of hacking in question is known as a distributed denial-of-service attack that fills websites with fake traffic to get them off the web. This is a common tool preferred by hacktivists, such as Killnet, non-governmental groups that carry out cyberattacks for political purposes.