Mobile phones connected to 4G and 5G networks will vibrate and emit a siren sound for up to 10 seconds

The official 'Emergency Alert' will be sent to all 4G and 5G-enabled phones and tablets. The devices will vibrate and emit a siren-like tone for ten seconds. Pictured: File photo

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Mobile phones connected to 4G and 5G networks will vibrate and emit a siren sound for up to 10 seconds

At around 3pm on Sunday, 7 September, all 4G and 5G mobile phones in the UK will blare a 10-second siren blast and display a test alert from the Government.

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.