David Cameron promises to clamp down on social media after London riots

Prime minister David Cameron has warned that social media and communications technologies such as BlackBerry Messenger and Twitter could be banned during times of social unrest in light of the riots that swept across England.

Speaking in the House of Commons, Cameron said that the government will review how social media was used to co-ordinate riots and looting in London, Manchester and other cities.

Cameron did not name any particular technologies in the speech, but BlackBerry Messenger and Twitter are thought to be the main tools used by the rioters to co-ordinate their plans.

"Everyone watching these horrific actions will be struck by how they were organised via social media. Free flow of information can be used for good, but it can be used for ill. When people are using social media for violence we need to stop them," he said.

"So we are working with the police, the intelligence services and industry to look at whether it would be right to stop people communicating via these web sites and services when we know they are plotting violence, disorder and criminality."

Cameron added that he has asked police whether they "need any other new powers", seemingly in reference to the monitoring and control of social media technologies.

V3 contacted RIM to ask whether it could switch off BlackBerry Messenger in certain areas as the prime minister seemed to be suggesting, but had received no reply at the time of publication.

V3 also contacted Everything Everywhere, O2, Three and Vodafone to ask whether they could block access to social media services, but again received no reply.

Jim Killock, executive director of the Open Rights Group, questioned Cameron's comments, arguing that the riots must not be used as an excuse to intrude on people's privacy, and urging companies to stand their ground in the face of any new legislation.

"If court procedures are not used, we will quickly see abuses by private companies and police. Companies like RIM must insist on court processes," he said.

"Citizens also have the right to secure communications. Business, politics and free speech relies on security and privacy. David Cameron must be careful not to attack these fundamental needs because of concerns about the actions of a small minority."

Several commentators, including Tottenham MP David Lammy, have called for BlackBerry Messenger to be shut down during any rioting, and the police are planning to use messages sent over the service to pinpoint the organisers.

Hampshire Police confirmed today on its Facebook page that it has begun arresting people suspected of using social networking services to instigate disorder, and is continuing to track down evidence of people attempting to incite rioting.

"Three people have been arrested on suspicion of using Twitter and BlackBerry Messenger to incite violent disorder in Southampton," the force said.

"Two remained in custody overnight and will be interviewed today, a third has been released on bail pending further inquiries. Our intelligence teams continue to monitor and take action against anyone using social media to attempt to cause riot."

The Metropolitan Police has posted photographs on Flickr in a bid to get the public to identify possible looters.