People in Norfolk may see their mobile phones emit an emergency siren on Tuesday, as the government tests its new system for major life-threatening events.

Several networks across the UK will today test the Emergency Alert system the government is bringing in.

Expected to launch this summer, the new alerts are being brought in to warn people if there is a danger to life nearby.

In the future when the service is live, an emergency alert may be issued for incidents like severe flooding, fires, explosions, public health emergencies and terrorist incidents.

They will only ever be sent by government departments or the emergency services.

On Tuesday, some Android phone users may get an alert between 1pm and 2pm at the system is tested.

Your phone or tablet may read out the alert, vibrate and make a loud siren-like sound – even if it's set on silent.

It will last for around 10 seconds.

For real alerts, people are told to stop what they are doing and follow the instructions given – but this will not be the case for the test.