(AP) -- Executives from Facebook, Twitter and BlackBerry maker Research in Motion Ltd. are meeting the British government and police Thursday to discuss how to prevent social networks from being used to plot violence.
Police and politicians claim young criminals used Facebook, Twitter and Blackberry's simple and largely cost-free messaging service to coordinate looting sprees during riots in England this month, and Prime Minister David Cameron has said police and intelligence services are looking at whether there should be limits on the use of social media sites or services like BlackBerry Messenger in times of disorder.
Civil libertarians have reacted with alarm to suggestions the services could be shut down in times of crisis.
A Home Office spokeswoman said there was "no suggestion" the sites would be closed down.
But she said the meeting would discuss "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."
The companies are likely to resist calls for curbs on their services.
Facebook said it already took down threats of violence and other offending material, and was working on making the process speedier.
"We look forward to meeting with the home secretary to explain the measures we have been taking to ensure that Facebook is a safe and positive platform for people in the UK at this challenging time," the company said in a statement.
Several people have been charged with using social media to incite riots, including two men who were jailed for four years each for using Facebook to "organize and orchestrate" disorder. The riots the two called for never happened.
A senior police officer revealed last week that the force had considered seeking approval to switch off such services like Twitter during the mayhem, but decided against it.
The acting chief of London's police force, Tim Godwin, told lawmakers that the legality of such action was "very questionable," and social networks were a useful intelligence asset.
Police said they sent officers to protect major London shopping centers and the 2012 Olympics sites after intercepting messages on Twitter and BlackBerry Messenger saying they were targets for rioters.
Explore further: Iran launches cyber crime unit: police