This academic study was published in March 2011, with the title 'Information control and terrorism: Tracking the Mumbai terrorist attack through twitter' and was discovered via Twitter today!

The study is behind a paywall:http://link.springer.com/article/10....796-010-9275-8

So here is the blog comment, first the author's bio:
Patrick Meier (PhD) is an internationally recognized thought leader on the application of new technologies for crisis early warning, humanitarian response and resilience.
It starts with, my emphasis:
Those who are still sceptical about the value of Twitter for real-time situational awareness during a crisis ought to ask why terrorists likely think otherwise. In 2008, terrorists carried out multiple attacks on Mumbai in what many refer to as the worst terrorist incident in Indian history. This study, summarized below, explains how the terrorists in question could have used social media for coordination and decision-making purposes.
The study concluded, in part:
...we conclude that the Mumbai Twitter page indirectly contributed to enhancing the situational awareness level of Mumbai terrorists, although we cannot exclude the possibility of its direct contribution as well....Because terrorists’ political goals function as interpretative filters to process situational information, understanding of adversaries’ political goals may reduce costs for security operation teams to monitor and decide which tweets need to be controlled.
Link:http://irevolution.net/2013/02/14/te...-used-twitter/

Ah, controlling tweets - now there is a dilemma. I do not understand the technology, but know a tweet can be withdrawn and the system can hinder activity. One wonders if anyone has thought through an operating protocol. Plus I assume Twitter is not the only provider.