Twitter announced a new alert service today that will notify users by SMS when a there's an emergency situation developing in their locale.

The new Twitter Alerts tool allows users to sign up for alerts from reputable organisations and receive crucial information via text message, rather than having to check their Twitter timeline.

Texts, which will also appear as pop-up notifications for users on iOS and Android, will be sent whenever a group like the Federal Emergency Management Agency or the American Red Cross in the United States mark a tweet as an alert.

Twitter Alerts builds on the Lifeline service Twitter debuted last year, in response to the devastating Japanese earthquake and tsunami.

Expanding the lifeline

In a post on its official blog, Twitter wrote: "Today, we're launching Twitter Alerts, a new feature that brings us one step closer to helping users get important and accurate information from credible organisations during emergencies, natural disasters or moments when other communications services aren't accessible.

"We know from our users how important it is to be able to receive reliable information during these times. With that in mind, last year we announced Lifeline (a feature that helps Japanese users find emergency accounts during crises), and since then, we've been working on a related feature for people around the world."

Currently the organisations involved are limited to the United States, Japan and Korea, but Twitter plans to expand the initiative to more countries in due course.