UK police are scanning social media sites in a bid to identify likely protesters at the state funded ceremonial funeral of Margaret Thatcher next week.
Police officers are monitoring social media, internet forums and BlackBerry messaging networks in the expectation that Margaret Thatcher's funeral procession next Wednesday will be targeted by protesters.
The possibility of demonstrations during the funeral has raised concerns that police may adopt the controversial tactic of making pre-emptive arrests.
Plans appear to be under way for different groups to demonstrate during the funeral, and to hold celebrations around the country on the same day.
Police concerns have been fuelled by the impromptu street parties which broke out on Monday evening in Leeds, Bristol, Brixton, Liverpool and Glasgow – some of which resulted in arrests after clashes with officers. There were celebrations in Belfast last night.
Police and security-service planning for Baroness Thatcher's funeral has been under way for three and a half years. Officers will probably be required to line the route from the Houses of Parliament to St Paul's Cathedral to make sure that the cortège is not stopped.
The protests present a logistical headache for the Metropolitan Police, whose officers will have to make sure the procession is not disrupted while respecting the public's right to voice an opinion on one of Britain's most divisive politicians.
A Met spokesman said: "London's police, the MPS, City of London and British Transport Police are working together to deliver a security operation for Baroness Thatcher's funeral. Given the nature of the event, our operation will use of a range of appropriate tactics." The Met's first large-scale challenge is likely to be handling anti-Thatcher protests this Saturday evening in Trafalgar Square – a part of London associated with the moment the former Prime Minister's power began to crumble as poll tax protests turned violent.
The Met has made "pre-emptive" arrests in recent years after gathering intelligence about high-profile demonstrations – most notably before the Royal Wedding in 2011. Scores of people were detained in its run-up.
Some of those arrested took their case to the High Court which ruled that, on the facts of the individual cases, the arrests were lawful. An appeal is set to take place this summer. At the time of the original case one of the arguments police used to justify the arrests was that they aimed to protect minority protesters from angry crowds.
Daniel, a 26-year-old from south London who was at Monday night's Brixton protest and is helping to organise something similar for Saturday evening, told The London Independent: "There's never been an event with such a publicity run-up. At Brixton, the samba band and a sound system just turned up. Something similar will happen on Saturday. People will come and there'll be a few portable sound systems there."
He believed protests would only turn violent if the police tried to stop people voicing their opinion. "It would be unwise of the police to come down hard," he said. "Even a heavy police presence will provoke a reaction."
The legislation that allows for pre-emptive arrests is narrow and human rights lawyers have warned against any pre-funeral sweeps.
Politicians from across the political spectrum urged members of the public who disliked Lady Thatcher or her politics to show restraint. Tony Blair said: "Even if you disagree with someone very strongly – particularly at the moment of their passing – you should show some respect." When asked if he was worried there would be similar celebrations when he dies, he said: "When you decide, you divide. I think she would be pretty philosophical about it and I hope I will be too."
The Tory MP Conor Burns, a regular visitor of Lady Thatcher, said she would have been pleased by the reaction. "Funnily enough the parties that we're seeing, the things in some of these mining communities and those young people opening the champagne in Glasgow – they're a remarkable tribute to her," he said.
"I remember telling her about the TUC Congress selling the Thatcher 'death party packs'. She said the fact that they felt so strongly about her more than 20 years after she left Downing Street was a tribute to the fact she had done something in politics rather than simply been someone."
Martin McGuinness, Northern Ireland's Deputy First Minister, said people should "resist celebrating", adding: "She was not a peacemaker but it is a mistake to allow her death to poison our minds."
Former miners in Easington, Co Durham, will mark the 20 years since their pit closed with a party on the day of her funeral. Alan Cummings, chairman of the Durham Miners' Association, said the timing of the events was "remarkable" and "one of those quirks", adding: "She couldn't be cremated on a better day."