Britons encouraged to ‘keep their cool’ for test of emergency alert system

Britons have been encouraged to "keep their cool" for a test of the national emergency alert system on Sunday.

At around 3pm, mobile phones connected to 4G and 5G networks will vibrate and emit a siren sound for up to 10 seconds.

It will mark the second test of the system – after the first in 2023.

Mobile phone users will also receive a message making clear that the alert is a drill.

The Government has used the system to issue real warnings five times, including in January during Storm Eowyn to warn people in Scotland and Northern Ireland about severe weather .

Approximately 3.5 million people across Wales and south-west England received an alert during Storm Darragh last December.

A 500kg unexploded Second

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