PRESS ASSOCIATION -- Facebook, Twitter and BlackBerry executives are to meet the Home Secretary to discuss whether their users should be blocked when they are plotting violence and criminality.
The likes of BlackBerry Messenger - a service which allows users to send free-of-charge real-time messages - was said to have enabled looters and yobs to organise their movements during the recent riots, leaving no paper trail.
Troublemakers also harnessed the power of the social networking websites to incite unprecedented levels of civil disobedience.
As politicians and experts debate the possibility of a clampdown on the technology in the future, Theresa May will hold talks with representatives from the social media industry to gauge how far the authorities could go with this.
A Home Office source said there was "no suggestion" that any of the sites would be closed down.
A Home Office spokeswoman said: "The Home Secretary will meet the Association of Chief Police Officers, the police and representatives from the social media industry.
"These discussions will help us determine how law enforcement and the networks can work better together. Among the issues to be discussed is whether and how we should be able to stop people communicating via these websites and services when we know they are plotting violence, disorder and criminality.
"Social networking is not a cause of the recent disturbances but a means of enabling criminals to communicate. We are working with the police to see what action can be taken to prevent access to those services by customers identified as perpetrators of disorder or other criminal action."
Facebook pointed out that it already prioritised its review of content on the site that is "egregious during sensitive times like the UK riots", with a view to further reducing the time it took to take such material down and "disincentivise bad actors on the site".
Delegates from Facebook, Twitter and BlackBerry maker RIM will be joined by Lynne Owens, assistant commissioner of central operations at the Metropolitan Police, and civil servants from the Foreign Office and Department for Culture, Media and Sport.