KYIV — Cyberattacks disrupted emergency alert systems in Russia and Ukraine within hours of a temporary truce ending on Sunday, officials from both countries reported on Monday.
Russia’s emergencies ministry said its mobile app was hit by a “massive cyberattack” that allowed attackers to send false information to the public. The ministry stated on Telegram: “Attention! The mobile application of the Ministry of Emergencies of Russia has been subjected to a massive cyberattack, enabling attackers to send false information to the public.”
Ukraine’s air raid alert system was also compromised, with false notifications warning of radiation and chemical threats in Kyiv and other areas. The Ukrainian Air Force confirmed the breach in a statement on Telegram: “The air alert app appears to have been subjected to enemy influence. There is no radiation threat! Stay calm and follow our updates on our channel.” Alerts sent between 22:47 and 22:49 local time on Sunday falsely declared a radiation hazard, a chemical attack threat, and a nuclear alert across Ukraine. Loudspeakers in Kyiv also broadcast recorded warnings instructing residents to take precautions.
Ukrainian officials attributed the attack to Russia, with the Center for Strategic Communications SPRAVDI stating on X (formerly Twitter) that the incident was the work of Russian hackers. Ukraine’s Center for Countering Disinformation warned that the app’s threat levels no longer corresponded to reality. Russia has not publicly attributed the attack to any specific group.
The temporary truce, which had lasted from October 27 to November 1, was the longest pause in fighting since the war began nearly five years ago. The ceasefire enabled a humanitarian mission to the Russian-occupied city of Oleshky in Ukraine’s Kherson region. Ukrainian Parliament Commissioner for Human Rights Dmytro Lubinets called the truce “an important step in our joint humanitarian efforts” with Russia.
The truce expired after Russia refused an extension, according to Kyiv. US-mediated talks between Russia and Ukraine are scheduled to resume later this month, though negotiations have been effectively frozen since February, when the United States and Israel launched joint strikes on Iran.
Separately, Ukrainian President Volodymyr Zelenskyy announced on Sunday that Ukraine would halt strikes on Russian oil refineries—a demand made by US counterpart Donald Trump—if Washington provided Patriot interceptor missiles to Kyiv. This offer follows ongoing discussions about military aid and conditions for de-escalation.
Both countries have accused each other of escalating cyber operations in recent months, with Ukraine’s digital infrastructure frequently targeted since the invasion began in 2022. Russia has similarly reported repeated cyber intrusions aimed at its government and emergency systems. The latest incidents underscore the growing role of digital warfare in the conflict, as traditional and non-traditional battlefields continue to overlap.