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Rude awakening for O2 customers after network runs surprise test of emergency mobile alert system

Sorry, there's no nuclear missile inbound. You have to go to work

Birds chirping, the gentle burbling of coffee brewing – these are the sounds we typically associate with the dawn hours.

Everyone, that is, except customers of O2, who arose this morning to a noise described as akin to a "nuclear siren" after the network performed an unannounced test of the UK's emergency alert system.

The two alerts, sent around 0745 and 0800, were accompanied by a forebodingly shrill beep, the kind of which you'd expect to hear if a cruise missile was heading to your house. Meanwhile, a disembodied computerised voice read out the alert's message, which said as follows:


*** This is a Test Message *** This is an O2 Test Message to test Cell Broadcast. No action required. In future, alerts like this one may be used to warn you about a danger to life in the local area. *** End of Test Message ***

You can listen to the alert in the embedded tweet below.

The text – which was also received by customers of MVNOs that use O2's network in Britain, including Giffgaff, Sky Mobile, and Tesco Mobile – disrupted lie-ins, and slightly more seriously, caused genuine alarm among some.

"Thought I'd get to sleep in late this morning, but no, @O2 thought that 7:30-45(ish) AM and 8:00AM were the perfect times to test their new emergency alert system," moaned one Twitter user.

"After receiving a loud, emergency alert message from you at 7:45am and again at 8am, my panic attack has just become slightly bearable. Couldn't you have done this in the afternoon?" said another.

This alarm is perhaps understandable, considering the UK was a latecomer to the adoption of Cell Broadcast alerts, and the public is largely unfamiliar with them. Elsewhere around the world, Cell Broadcast is used to warn of everything from tornadoes and earthquakes, to missing children.

The tech has been adopted in the US, South Korea, Japan, and New Zealand, to name just a few. Additionally, the European Union has created its own standard for Cell Broadcast messaging, called EU-Alert. This has formed the basis for systems in the Netherlands, Lithuania, Romania, and Greece.

The UK government first started exploring the use of mobile alerts during the Coalition years. Between 2013 and 2015, the Cabinet Office evaluated the technology, launching trials in North Yorkshire, Glasgow, and Suffolk. Later tests were carried out in 2018 and 2019, in partnership with the Environment Agency, EE, and the University of Hull.

Despite the rude awakening, O2 subscribers can at least take comfort in the fact that they're not about to experience the kind of dystopian nuclear afterlife depicted in the brutally bleak TV film Threads.

And it could have been worse. In 2018, a rogue Cell Broadcast message warned Hawaiians of an incoming ballistic missile, prompting a mass scramble for shelter. It took 38 minutes for the local authorities to fess up to the mistake. ®

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