New Zealanders are being told not to be alarmed when their phones sound on Sunday evening as part of a nationwide test of the Emergency Mobile Alert (EMA) system.

NZ Civil Defence will test the system on Sunday 14 June, between 6pm and 7pm.

Police are also sharing an important safety message for anyone who has a hidden second phone for personal safety reasons.

Police said on their Facebook page that people with a hidden phone should turn it off or put it in flight mode for the duration of the test to ensure it is not discovered when the nationwide alert is sent.

Some mobile devices set to silent mode may still make a loud sound when the EMA is received, meaning switching to flight mode or turning the device off is the only way to avoid the alert sounding.

The EMA system is used to send urgent messages to capable phones and SIM-connected devices in areas affected by serious hazards.

Alerts are broadcast from targeted cell towers and can be used by authorised emergency agencies, including Police, Fire and Emergency New Zealand, the Ministry of Health, the Ministry for Primary Industries, the National Emergency Management Agency, and local Civil Defence Emergency Management Groups.

Officials say the nationwide test is carried out to make sure the system is working properly across the country.

Most phones and SIM-connected devices purchased in New Zealand after 2017 should be able to receive EMAs as long as they have cell reception and up-to-date software.

People do not need to download an app or subscribe to receive the alerts.

Anyone who does not want to receive the test alert needs to turn their phone off or put it into flight mode during the test window.

People experiencing family violence or who are concerned about someone’s safety can call 111 if there is immediate danger. Free, 24-hour support is also available through Women’s Refuge on 0800 733 843, Shine on 0508 744 633, and Are You OK on 0800 456 450.