When Russia initiated its full-scale invasion of Ukraine, a second, less visible battle in cyberspace got under way. The conflict has blurred the lines between those working for the military and the unofficial activist hackers. Oleksandr, one of the most prominent hackers in the vigilante group, the 200,000-strong IT Army of Ukraine, has helped to temporarily disable hundreds of Russian websites, disrupted services at dozens of banks and defaced websites. For over a year, he has devoted himself to causing as much chaos in Russia as possible. He recently joined a team of hackers called One Fist, to hijack Russian radio stations and broadcast the sound of fake air raid sirens and an alert message telling citizens to take shelter. ‘We feel ourselves like the military’, says Oleksandr. ‘When my country calls me to pick up a rifle I am ready, but hacking Russia now, I feel that I am helpful.’