The Government will issue an Emergency Alert to millions of mobile phones and tablets across the UK today (April 23).

A loud alarm will be emitted and will vibrate at 3pm as a new public alert system is trialled.

The message will be received on 4G and 5G mobile phones and the sound and vibration will last for up to 10 seconds, even if mobile phones are on silent.

Those who receive the alert will need to simply click the message or swipe it away as it appears on their device.

Once the Emergency Alert is clicked or swiped away, members of the public will be able to use their devices as normal.

Why is there an Emergency Alert?

An Emergency Alert will be received by millions today so that the new system can be tested.

The system is similar to those in the US, Canada, the Netherlands and Japan and is intended to be used in life-threatening situations including flooding and wildfires.

Alerts will only be sent by the emergency services or government departments, agencies and public bodies that deal with emergencies.