Ukraine's popular air raid alert app was apparently subjected to hostile interference on Sunday, sending false alarms of radiation and chemical threats to users in the capital, Kyiv. The Ukrainian Air Force confirmed the incident via Telegram, stating, "The Air Alarm application has probably been subjected to hostile interference. There is no radiation threat! Stay calm and follow our updates on our channel."

The false alerts began around 22:47 local time, with initial messages in Ukrainian warning of a "Radiation threat. Radiation threat declared in Kyiv." This was followed by an alert in Russian stating, "Hi! There will be a nuclear alert across Ukraine. Don't worry, it's Oreshnik flying." Subsequent alerts at 22:49 warned of a "Chemical threat. There is a threat of a chemical attack on Kyiv. Don't go outside," and a "Street fighting threat. Street fighting is taking place in Kyiv. Don't go outside."

In the Lviv region, the false "Radiation Hazard" signal was reportedly played on loudspeaker devices, according to the Ukrainian Central Intelligence Agency. This agency also stated there had been a "failure in the app" and urged the public to rely on other sources for information regarding air strike threats. They advised citizens to enable smartphone notifications, heed sirens, and consult only official sources for verified information.

The governor of Vinnytsia oblast, Natalya Zabolotna, confirmed the event as a cyberattack on the Air Alert app and cautioned users on Telegram against clicking any links within the fraudulent messages. The app, which is supported by Ukraine's Ministry of Digital Transformation, is designed to provide instant notifications about the commencement and conclusion of air defense alerts.

The incident highlights the ongoing vulnerability of digital infrastructure to cyber warfare tactics during the conflict. Adversaries have previously targeted communication channels and public alert systems to sow confusion and fear among the civilian population.

Following the false alarms, a series of "all clear" messages were sent to users' phones, each individually canceling the preceding false threat notifications. These messages were designed to correspond with the specific fake alerts that had been broadcast.

Authorities are investigating the source of the cyberattack and the extent of the interference. The Ukrainian Central Intelligence Agency's prompt response and advisories aimed to mitigate panic and reinforce reliance on trusted official communication channels.

This event underscores the importance of robust cybersecurity measures for critical civilian infrastructure and the need for public vigilance against disinformation campaigns, particularly in times of conflict.