France is to introduce a new system, called FR-Alert, which will enable authorities to alert everyone in a particular area of a major incident.
The scheme will allow officials to send a text message a number of localised people without the need for an app.
The system, to be launched at the end of this month, will boost communications from French emergency services, such as those on social media and news alerts.
It will be used for emergencies and major incidents such as terrorist attacks or severe flooding.
Any phone receiving the new alerts — even if it is on silent — will make a noise and vibrate.
The message will contain details of the risk, its location, and any behaviour required by people in that area to ensure their protection.
Messages will be sent in French, although authorities say there is scope for other languages to be used if an incident takes place in an area popular with tourists.
Officials carried out tests of the new system in the Rhone area on Tuesday.
"The population alert and information system #FrAlert is being tested today in the Rhone department. If you are in the exercise zone, you may receive an alert notification," security officials said.
France's Interior Ministry said the system would be used for “any type of major event that justifies alerting the population concerned to ensure their safety”.
"FR-Alert makes it possible to notify anyone with a mobile phone in real time of their presence in a danger zone in order to inform them of the behaviour to adopt to protect themselves," it said in a statement.
"It will make it possible to alert the population in a few seconds."
The ministry said a number of security exercises were being carried out in which "the sending of the alert notification will be tested".
"If residents are in one of the areas determined by the exercise scenario, you will be able to receive a notification accompanied by a specific sound signal, even if your mobile phone is in silent mode," it said.
