Ukraine’s Main Intelligence Directorate (HUR) has allegedly attacked Russia’s tax system, destroying the entire database and its backup copies, according to a statement by the intelligence agency on Tuesday. HUR claims Russia will be unable to fully restore its tax system.

“During the special operation, military intelligence officers managed to penetrate one of the well-protected key central servers of the Federal Taxation Service (FTS of the Russian Federation), and then more than 2,300 of its regional servers throughout Russia, as well as in the temporarily occupied Crimea,” HUR said.

The cyberattack infected all servers with malware, paralyzing communication between the central Moscow office and 2,300 regional Russian tax offices, as well as between the FTS and the IT company Office.ed-it.ru that served as the tax data center, according to HUR.

HUR states the attacks completely destroyed the infrastructure of a core Russian state agency and numerous associated tax data over an extended period. Additionally, Russia’s nationwide tax data traffic is now under Ukraine’s military intelligence control.

HUR remarks that the attacks effectively eliminated configuration files built up over years that enabled the FTS’s extensive system to function, wiping out the entire database and backup copies.

“The Russians have been unsuccessfully trying to restore the tax service for four days in a row. According to experts, the paralysis in the work of the FTS of the Russian Federation will last at least a month. At the same time, the complete resuscitation of the aggressor state’s tax system is impossible,” HUR said.

Earlier today, Ukraine’s top mobile operator Kyivstar and bank Monobank suffered a hacker attack allegedly originating from Russia.