It will mark the second test of the national emergency alert system – after the first in 2023

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

It will mark the second test of the national emergency alert system – after the first in 2023

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