Russia warned the West that cyber attacks against its infrastructure could lead to direct military confrontation, and that attempts to challenge Moscow in the cyber sphere would be met with targeted countermeasures.
The warning came after Russia's housing ministry appeared to have been hacked over the weekend, with an internet search for the site leading to a Glory to Ukraine sign in Ukrainian.
In a statement, the foreign ministry said Russia's critical infrastructure and state institutions were being hit by cyberattacks and pointed out figures in the United States and Ukraine as being responsible.
Russia will not leave aggressive actions unanswered, it said. All our steps will be measured and targeted in accordance with our legislation and international law. The ministry's head of international information security, a statement, said Washington was deliberately lowering the threshold for the use of cyberweaopns.
The threat of a direct military clash with unpredictable consequences has been increased by the militarization of the information space by the West, and attempts to turn it into an arena of interstate confrontation, it said.
Since Russia invaded Ukraine on February 24, the websites of many state-owned companies and news organisations have suffered sporadic hacking attempts to show information that is at odds with Moscow's official line on the conflict.
Moscow says it is carrying out a special military operation in the neighbouring country to disarm it and protect it from fascists. Ukraine and Western countries dismiss Russia's claims as a pretext for an illegal invasion.
President Vladimir Putin said in May that the number of cyberattacks on Russia by foreign state structures had increased several times and called for the country to strengthen its IT security.