Ukraine President Volodymyr Zelensky has shamed NATO for leaving his countrymen alone to fight. One group that has vowed to go up against Russia is the infamous hacking group “Anonymous.” On Thursday evening the group tweeted “The Anonymous collective is officially in cyber war against the Russian government.”

Even before the physical attack against Ukraine with troops and missiles, Russia is believed to have carried out the massive cyber-attack against the Ukrainian government and banks. Twitter users thanked the online group for making the pledge against Russia.

Daily Mail reports “Anonymous have previously targeted groups including the Ku Klux Klan and Islamic extremists.” The members are known “as ‘Anons’ and are distinguished by their Guy Fawkes masks.”

The group threatened Tesla founder Elon Musk that they would target him because they believed he had too much power over the cryptocurrency markets. While some are praising their decision to go after Russia, dozens of individuals involved in the group have been arrested for their involvement in cyberattacks.

They have a global presence, and arrests have been made in the U.S., UK, Australia, the Netherlands, Spain and Turkey. Deemed “hacktivism”, targets of Anonymous have included governments agencies of the United States, Israel, Tunisia, Uganda, and others.

The group has also gone after copyright protection agencies and corporations such as PayPal, MasterCard, Visa and Sony.