Ukraine's Air Raid Alert App Hacked, Sending False Radiation and Nuclear Warnings to Users

At 22:47 on Sunday night, phones across Ukraine running the Air Alert app lit up with red-level air raid warnings, apparently issued nationwide. Within minutes, users in Kyiv were reading something far worse. The first message, in Ukrainian, said: "Radiation threat. Radiation threat declared in Kyiv."

The Ukrainian Air Force later said the app had apparently been hacked. More messages followed in quick succession. At 22:48 came one in Russian: "Hi! There will be a nuclear alert across Ukraine. Don't worry, it's Oreshnik flying." At 22:49 a chemical alert warned of a possible chemical attack on Kyiv and told people not to go outside. A fourth alert, also at 22:49, claimed street fighting was under way in the capital and again told residents to stay indoors.

The Air Force responded on Telegram, saying the app had probably been subjected to hostile interference. "There is no radiation threat," it wrote, urging people to stay calm and follow its channel. Ukraine's Central Intelligence Agency described a failure in the app and asked people to use other sources to check on the threat of air strikes. At 23:53, users received a series of all-clear messages, each declaring one of the earlier Kyiv threats over.

The effects reached beyond phone screens. The intelligence agency said the app caused the radiation hazard signal to sound on loudspeaker devices in the Lviv region, and stressed there was no such hazard. Regional leaders also went online to calm residents. Svitlana Onyshchuk, governor of Ivano-Frankivsk Oblast, said everything was calm for now; the app had shown a red-level air raid alert for the oblast between 22:50 and 23:57. Natalya Zabolotna, head of the Vinnytsia region, confirmed a cyber-attack on the app and warned people not to click a link in the message, which could be a phishing attempt.

The Air Alert app is supported by Ukraine's Ministry of Digital Transformation and is designed to tell users immediately when defence alerts begin and end. The ministry said it had temporarily disabled the app for maintenance after it was apparently compromised, and asked residents to turn on emergency notifications on their smartphones so they could still receive state-issued warnings. Ukraine's Centre for Countering Disinformation gave similar advice: enable notifications, listen for sirens, and rely only on official sources.

A few hours later, Russia's ministry of emergency situations said its own app had suffered "a massive cyberattack" that sent "fake information to the public." Neither the ministry nor state media gave further details. The Ukrainian outlet UNN reported that the hack sent fake warnings of a nuclear threat inside Russia. Atesh, a Ukrainian partisan group operating in Russian-held territory, claimed the hack on its Telegram page, with laughing emojis. It posted a screenshot of a purported alert telling users to urgently stock up on three weeks of provisions and take cover in basements, and using obscene language. The BBC has not verified the screenshot and has contacted Atesh for comment.

The nuclear framing carries weight: Russia has the world's largest nuclear arsenal, and President Vladimir Putin has repeatedly signalled openness to using all weapons at Russia's disposal.

The timing also stands out. The false alerts began shortly before the end of a localised ceasefire in the front-line Kherson region, which took effect last Tuesday and officially expired at 23:00 on Sunday. It was meant to let civilians leave the Russian-occupied city of Oleshky, while fighting continued elsewhere. Russia launched its full-scale invasion in February 2022. For now, officials in both countries are asking people to trust sirens and official channels over the apps, and the details of how each was breached remain unexplained.