A controversial nationwide emergency alert system which was transmitted to millions of phones across the UK this afternoon was hit by technical issues – arriving late on some phones, and not all for others.
Devices connected to 4G and 5G networks throughout Britain blared a siren-like alarm, vibrated and displayed a warning message for ten seconds at around 3pm – even if they were on silent.
It was the first test of its kind since 2023 and has been criticsed over ‘big brother’ concerns over intrusion of the state into private life.
Experts have warned the unexpected alarm could put people at risk of heart attacks, and compromise the safety of abuse victims by blaring on phones hidden from their partners.
Fans at sporting events throughout Britain were spotted in the stands looking down at their phones as the alerts rang out, with TV broadcasters also primed to react as it played out.
But in a flop for the emergency system, which will cost up to £25.3million to fund during its first three years, presenters live on BBC News were forced to fill air time as the siren failed to come through when expected.
Titled ‘Severe Alert’, the notification which eventually came through read: ‘This is a test of Emergency Alerts, a UK government service that will warn you if there’s a real life-threatening emergency nearby.’
While today’s notification was a drill, real warnings are reserved for risk-to-life scenarios such as large fires, flooding or terror attacks – and have been issued five times in the past.
It was deployed in January to warn millions of people in Scotland and Northern Ireland of the dangers of Storm Eowyn.
A big screen message reminded fans of the Emergency Alert test at the Women’s Rugby World Cup tie between New Zealand and Ireland
Many inside the cinch Stadium stopped to look at their phones as the alarms blared out
And around 3.5million people across Wales and south-west England received an alert during Storm Darragh last December.
Warnings have also been sent in more unique circumstances, like when a 1100lb unexploded World War II bomb was found in a garden in Plymouth in February 2024 – triggering an alert to 50,000 residents.
The system was first introduced in 2023, when former Cabinet Office minister Baroness Neville-Rolfe revealed that it would cost ‘a maximum of £25.3million’.
Some £5million of this was for a contract with Fujitsu – a Japanese IT firm – as well as a further £18.6million to mobile network providers and for security tests and legal work.
Labour MP Darren Jones thanked the public for ‘taking part’ in today’s practice alert and said it will ‘help the government keep the country safe 24 hours a day, 365 days a year’.
A government spokesperson responded: ‘We have not identified any widespread issue with incorrect messages.
‘The alert message was broadcast correctly and mobile operators have confirmed that the test ran as expected. Where a message may have appeared incorrectly, this is likely due to issues with individual mobile handsets.’
However, scores of unimpressed Britons rushed to social media to mock the system after receiving the alert late – calling into question what would happen in a real emergency.
One person jibed on X at 3.09pm: ‘Well that emergency alert was six minutes late!! If it had been a nuclear alert I’d have had no time to hide under the table.’
Another added at 3.19pm: ‘My emergency alert was 18 minutes late i’m gonna be f****d if there’s a real one.’
Britons rushed to social media to say their alert was late as they mocked the slow system
A third wrote at the same time: ‘It’s damn reassuring to know that when an emergency alert needs sent out it will be AT LEAST 20 MINUTES LATE. Wonder if I wait long enough, three will come along at once. Typical government reliability.’
In other cases, some reported online that they were entirely missed by the alert.
A poster wrote at 4.06pm: ‘Didn’t get the alert again. It’s never gone off on my phone. Was in a very busy supermarket at the time, very few phones went off.’
One woman, whose phone buzzed three times at 3.07pm, said: ‘[Don’t worry] if you didn’t get the alert today, I was clearly allocated your message because I got it 3 times.’
Emergency planners in the Cabinet Office Briefing Rooms (COBR) Unit chose 3pm for what was dubbed the ‘Armageddon alarm’ in a bid to minimise disruption.
The largest public safety exercise of its kind, it will have been sent to around 87million phones in the UK, with the government saying around 95 per cent of the population has 4G or 5G access.
The alarm, first introduced in 2023, is designed to deliver ‘life-saving information’ in times of crisis, such as during a wildfire or storm.
But experts warned that the test carried its own set of risks. One acute stress response specialist said the emergency alarm could trigger heart attacks in some people as it would cause a ‘flight-or-fight response’.
Fans in the stand react as the emergency national alert system test goes off, during the Women’s Rugby World Cup 2025 pool D match at cinch Stadium at Franklin’s Gardens
An Emergency Alert on the screen of a smartphone in central London today
At 3pm today, millions of mobile phones vibrated and made a siren sound for roughly ten seconds. The Globe Theatre (pictured) paused its performance
The loud sound of the emergency alert (pictured) may activate the body’s flight-or-fight system, triggering an increase in heart rate, a spike in blood pressure, and a flood of stress hormones
This is due to research showing that emergency alarms can cause participants’ heart rates to spike from an average of 74 to 111 beats per minute or higher.
Other campaigners fear it may expose hidden phones used to seek help by abuse victims and could have terrifying consequences for those hiding devices from controlling or violent partners.
They urged anyone with a hidden device to disable emergency alerts ahead of the drill.
There were also worries that the alert could ‘trigger’ people with epilepsy.
Nicola Swanborough, Head of External Affairs at the Epilepsy Society, warned that people with the condition could suffer ‘seizures triggered by loud noises, such as the siren-like sound of the test’.
The alarm even prompted the Globe Theatre to announce that it would pause a performance of Shakespeare’s Twelfth Night so that the alarm did not disrupt the play.
The Government insists the alert — which is also used in countries like the US and Japan — is a life-saving measure, and says it will only be deployed in extreme circumstance such as flooding, fires or terror attacks.
Pat McFadden, the newly appointed Secretary of State for Work and Pensions, said: ‘It’s important to remember this is only a test, just like the fire drills we all do in our schools and workplaces.
The alert system was used in Plymouth after an unexploded World War II bomb was uncovered and had to be removed
‘We’re carrying out the test to make sure the system works well when we need it most, and afterwards, we’ll work with mobile network operators to assess performance.
‘The test takes just ten seconds, but it helps us keep the country safe 24 hours a day, 365 days a year.’
In the lead-up to the test, there were announcements and signs telling the public to save the date, including adverts on motorways, railway and bus stations, museums, GP surgeries, concert venues and theatres.
However, due to the concerns raised by charities, the Government has made it possible for those concerned to opt out of the alerts.
This can be done on an iPhone by going to ‘settings’ and selecting the ‘notifications’ menu, then scrolling to the bottom and turning off ‘severe alerts’ and ‘extreme alerts’.
If on an Android device, search your device settings for ’emergency alerts’ and then turn off ‘severe alerts’ and ‘extreme alerts’.
The government webpage says people should contact their device manufacturer for help if they are still getting alerts after opting out.
Also, depending on the manufacturer and software version of your phone, emergency alerts settings may have different names.
These might include ‘wireless emergency alerts’ or ’emergency broadcasts’.
The alarm was the first time that the Emergency Alerts System had been tested in two years, following the system’s launch in 2023.
Phones also displayed a message stating that the alarm is only a test and not a genuine threat to life.
Data about you and your device was not collected or shared in any way during the test, regardless of whether you received the alert or chose to opt out.
A step-by-step guide on how to turn off the alert on iPhone and Android devices
Since the message is sent automatically via the mobile networks, the government does not need your phone number to send alerts, so your number will not be stored.
Similar systems are already used widely across a number of other countries, primarily for natural disaster preparation.
Japan has one of the world’s most sophisticated systems, which combines satellite and cell broadcast technology.
This system forms part of a wider scheme called J-ALERT that informs the public in case of earthquakes, tsunamis, volcanic activity or missile threats.
South Korea frequently uses its national cell broadcast system to alert citizens about issues ranging from weather alerts and civil emergencies to local missing persons cases.
The US has a similar system to the UK that utilises ‘wireless emergency alerts’ to send messages that look like texts with a unique sound and vibration pattern.
