Thousands of hackers and IT specialists around the world are helping to defend Ukraine, and some are doing so by targeting Russian organizations with cyberattacks, a senior Ukrainian government cybersecurity official said on Friday.

According to Victor Zhora, an official with Ukraine’s cybersecurity agency responsible for protecting government networks.

The “computer army” is a loose group of Ukrainian citizens and foreigners who are not part of the Ukrainian government – but Kiev encourages them. It’s an example of how the Ukrainian government is pulling out all the stops to try to slow down Russia’s military onslaught, and illustrates how cyberattacks have played a supporting role in the war.

The goal of Ukraine’s “IT army” is to “do everything possible…to make [the] the aggressor feels uncomfortable with his actions in cyberspace and on Ukrainian soil,” Zhora told reporters in a video conference Friday.

Hacktivists from a variety of backgrounds — from war-opposed Belarusians to self-proclaimed Russian hackers — have entered the information war and claimed to have hacked their opponents.

The website of Russian state media TASS was hacked on Monday and briefly posted a message referring to Russian victims of the war in Ukraine and denouncing Russian President Vladimir Putin. Although it is unclear who was responsible for the hack, the logo of hacking collective Anonymous appeared on the TASS website.

More background: Calling for volunteer hackers last Saturday, Ukraine’s Digital Transformation Minister Mykhailo Fedorov tweeted a link to a list of potential targets that included major Russian energy and financial companies.

Zhora claimed that any hacking carried out by the “IT Army” was defensive in nature and that the Ukrainian government bears no responsibility for cyberattacks the volunteers carry out against Russian organizations.

Ukrainian cybersecurity officials are continuing their work to protect government networks despite Russian bombardment of key Ukrainian cities, Zhora said.

“We are not afraid” of any escalation in cyberspace from Russia, Zhora said.

“We are much more afraid of missiles targeting Ukrainian schools, hospitals and residential areas,” he continued.