Test of the ‘LU-Alert’ public warning and information system, involving the sending of a ‘silent’ cell broadcast (6 July 2026)

On Monday 6 July 2026, the government will continue to implement its strategy for testing the ‘LU-Alert’ public warning and information system by carrying out the monthly test of the siren network.

In addition, the mobile cell broadcast (CB) alert channel will be tested at around 11.00 am across the whole of the country; however, this alert will be silent. The message will appear as a priority notification on the screens of mobile devices, even when they are in silent or locked mode. Please note that no audible signal or vibration will be emitted.

To ensure that the alert is effectively received without sound, it is essential that mobile devices are running a version compatible with receiving such messages via the ‘LU-Alert’ system and are up to date^[1]:

• Apple: iOS 17.5 or later with the June 2024 system update;
• Android: Android 11 or later with the system update of 1 August 2024.

As with previous tests, the test alert transmitted via the mobile network will be broadcast simultaneously via the ‘LU-Alert’ mobile app and on the website www.lu-alert.lu. As this is a test alert, there is no need to react or take any specific action.

The Ministry of the Interior would like to remind the public that the authorities use this alert channel when the event requiring the public to be alerted or informed is likely to pose a significant or imminent danger to the population and immediate action is expected of them. In particular, the silent alert is suitable for situations requiring a discreet warning.

Further information and a list of frequently asked questions are also available on the website www.lu-alert.lu.

Issued by : ministère des Affaires intérieures / Corps grand-ducal d’incendie et de secours