KYIV, Ukraine — Authorities in Ukraine and Russia said their emergency alert mobile apps had been targeted by cyberattacks with users in Ukraine receiving false warnings of an imminent nuclear threat.
It was not clear if the attacks late Sunday were related. Ukraine said its service, which residents rely on to seek safety amid daily Russian missile and drone strikes, was up and running again after being suspended due to the attack.
Russian authorities said Monday that hackers had sent fake emergency alerts after gaining access to the Russian Emergency Situations Ministry’s mobile app, and that efforts were ongoing to restore the app's functionality.
A Russian Telegram channel said a hacking group, Hitcore, had claimed responsibility for the breach of the Ukrainian system, but that could not be independently verified. Any affiliations or other details surrounding the identities or motivations of the purported hackers were unclear.
The alerts received by Ukrainians — making false claims of high radiation levels, a chemical threat and public disturbances in Kyiv — were written in English with spelling and grammatical errors as well as in a mix of Russian and Ukrainian.
One of the messages, written in Russian, said: “Hi! There will be a nuclear threat across Ukraine. Do not worry, the Oreshnik is incoming,” a reference to a Russian intermediate-range ballistic missile.
In a Telegram post late Sunday following the breach, Ukraine’s air raid alert channel said “unauthorized parties” had interfered with the app’s operation and warned users not to click on links in “suspicious notifications.”
Ukraine's state-run Center for Countering Disinformation reported the breach and urged users to monitor other emergency channels on social media and rely on physical alerts while the cyberattack was being addressed.
Yurii Ihnat, a spokesman for Ukraine’s air force command, said the cyberattack had no impact on Ukraine’s security and defense operations because the app is separate from military command systems.
Ihnat told Ukraine’s private 1+1 television that the air force continues to report real-time threats through independent communication channels, including popular social media platforms.
In a statement, Russia’s Emergency Ministry said that hackers had used its mobile app to send a false alert across 33 of Russia’s 89 regions at approximately 2:45 a.m. Moscow time (11:45 p.m. GMT). It did not name who it believed carried out the attack.
The ministry said that the digital vulnerability exploited by the attackers had been identified and that “necessary measures” were being taken to prevent a similar breach. It also reassured Russians that the wider public alert system was working normally through SMS messages, media broadcasts and municipal sirens and loudspeakers.
Kremlin spokesperson Dmitry Peskov said that all of Russia’s state agencies were under the constant threat of cyberattacks, including a growing number that use artificial intelligence.
“All government bodies must take steps to improve the cybersecurity of our digital resources,” Peskov said.
Limited ceasefire ends in Kherson region
Ukrainian authorities in the war-divided Kherson region reported multiple Russian drone attacks early Monday, hours after a humanitarian ceasefire expired.
The regional administration said a 62-year-old woman and a 73-year-old man were hospitalized with blast injuries in the city of Kherson, across the Dnipro River from Russian-occupied territory.
The localized ceasefire ended at midnight at the start of Monday. The brief pause in fighting was tied to a humanitarian aid mission in the Russian-occupied city of Oleshky.
The ceasefire, which began Oct. 27, marked the most significant truce between Kyiv and Moscow since Russia's full-scale invasion of Ukraine began nearly five years ago.
The White House said U.S. first lady Melania Trump helped broker the limited truce. Civilian negotiators from Russia and Ukraine also helped secure the pause, which allowed besieged residents of Oleshky to be evacuated in a rare joint operation that ended Saturday.
An estimated 2,000 civilians were in Oleshky when the temporary truce took effect. They could evacuate to territory controlled by either Ukraine or Russia, or remain in the city with replenished food and medical supplies. Exact evacuation totals were withheld to protect those who stayed.
Ukraine’s general staff said Monday that Russia’s military had bolstered its drone defenses and replenished ammunition supplies in the area during the ceasefire.
Elsewhere in Ukraine, emergency services reported that drone strikes injured 12 people in the eastern Kharkiv region and damaged a refrigeration facility, greenhouses and residential buildings.
Five people were also reported injured in the Black Sea port city of Odesa, where a warehouse was targeted and homes were damaged.
Russia’s Ministry of Defense said Monday that it had shot down 212 Ukrainian drones overnight, while the head of Russia’s Samara region, Gov. Vyacheslav Fedorishchev, said in a statement that local air defenses were repelling an aerial attack, but did not give further details.
Independent Russian media outlets later reported that Ukrainian drones had targeted one of Europe’s largest oil transport hubs in Russia’s Samara region.
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Katie Marie Davies contributed to this report from Manchester, England.
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