A new public alert system is being tested for the first time in public places across the country at midday.

NL-Alert messages will be displayed on around 1,200 advertising screens at bus and tram stops, train stations and in shopping centres at around midday. Tests will also be sent to mobile phones to check that people’s devices are calibrated with the emergency messaging system.

The twice-yearly alerts were sent to mobile phones for the first time in December last year and will eventually replace the monthly test of the air-raid sirens, which is due to end next year.

The government says using digital screens and mobile phones will allow it to distribute more information more efficiently if there is an emergency, including details of where to go and how to respond.