Twitter has today launched an alert service to allow the public to keep track of developments at times of crisis or emergency.
The social network has got 57 accounts on board for the programme, including the Mayor of London's office, the London Fire Brigade and the UK's 47 police forces.
Such organisations will use Twitter to push out urgent information to their followers by marking their tweets as alerts. Those messages will be highlighted with an orange bell to emphasise their importance.
Users who sign up for an account's Twitter alerts will receive notifications in the form of text messages sent directly to their mobile phones. Android and iPhone users will also be sent push notifications.
The Met Police's emergency planning chief David Martin said: "Getting fast and accurate information to the public in a major incident or terrorist attack really could make a life-saving difference.
"Using social networking sites, including Twitter, gives us additional ways to talk directly to the public. Twitter Alerts means that our messages will stand out when it most matters."
The service, which launched in the UK and Ireland today, has been used by participating organisations in the US, Japan and Korea since September.
It is intended for crisis, disaster and emergency communications, according to Twitter - although those organisations which sign up to the scheme can choose their own which tweets warrant 'alert' status.
The London Fire Brigade's Deputy Commissioner said: "People act on information shared on social media.
"During a major incident accurate, verified and frequent updates are essential. Twitter Alerts will help us communicate quickly during a significant emergency."
