A nationwide test of the Emergency Mobile Alert will take place Sunday evening between 6pm and 7pm.

Anyone with their mobile phone switched on will receive the alert, the National Emergency Management Agency (NEMA) said.

Director John Price said the mobile alert was one tool used to communicate to the population when their life, health or property was in serious danger.

"The test allows NEMA to check that the Emergency Mobile Alert system is working as it should, and gives you a chance to check that your phone is receiving the alerts."

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Alerts could be targeted to specific regions or cities when they were under threat, he said.

"If you get an alert, you must stop and read the message, and take it seriously. It will tell you what the emergency is and what to do. It will also tell you which agency sent the message and, if needed, where to go for more information."

The alerts did not replace other ways to stay informed, or the natural warning signs that could indicate danger, he said.

"Please act immediately if you feel your life is in danger. Don't wait for an alert, don't wait for an official warning - just get yourself to safety.

"For example, if flood waters are rising - self evacuate and move to higher ground. If you are near the coast and an earthquake is long or strong, get gone - move immediately to the nearest high ground, or as far inland as you can."