Britons urged to ‘keep their cool’ as siren-like sound to emit from millions of devices on Sept 7 at 3pm

At about 3pm this coming Sunday all 4G and 5G mobile phones in the UK will blare a 10-second siren blast and display a test alert.

Millions of UK phones to sound siren in national emergency alert test, part of government resilience efforts.

Devices will vibrate and make a siren sound for 10 seconds at 3pm, with message confirming alert is a test

It marks the second test of the national emergency alert system after the first in 2023

Millions of phones will emit a siren sound and vibrate during the drill

It marks the second test of the national emergency alert system after the first in 2023

Secretary of State Pat McFadden said he knows Brits will 'keep their cool' when their phones make a siren-like noise for 10 seconds, vibrate and show a message.

Britons urged to ‘keep their cool’ as siren-like sound to emit from millions of devices on Sept 7 at 3pm

Phones across the country play siren and vibrate in latest test of service for use during emergencies

At around 3pm, mobiles connected to 4G and 5G networks throughout Britain vibrated and sounded for about 10 seconds in the second test of the system.

Millions of phones sounded and vibrated during the test

LONDON: Millions of mobile phones across the UK blared a siren sound at the same time on Sunday as part of government efforts to better prepare for national emergencies. The…