We will never buckle to terror': Cameron spreads defiant message online that Britain will face down threat from extremists

We will never buckle to terror': Cameron spreads defiant message online that Britain will face down threat from extremists The attack has been roundly condemned David Cameron will today chair a meeting of the government's emergency committee after issuing a defiant message that Britain will ’never buckle’ to terrorists in the wake of the horrific knife attack in Woolwich. The Prime Minister last night used his personal Twitter account to vow to face down the threat posed by extremists. As Mr Cameron prepared to return to London to take charge of the government’s emergency response, he chose to use social media to spread the message: ’We will never buckle to terror.’ Did you witness the killing and take pictures or video of the appalling incident? Or do you know the men involved? Email us at mailonlinepictures@dailymail.co.uk The Prime Minister cancelled talks with French President Francois Hollande in Paris to travel urgently to back to London. Mr Cameron described the attack as ’truly shocking’ and 'the most appalling crime' after reports suggested a soldier wearing a Help for Heroes t-shirt was attacked by two men wielding machete-style knives. He had been at an Brussels summit before travelling to Paris but tore up his schedule to receive a detailed telephone briefing on the latest from Woolwich from Home Secretary Theresa May. Last night she chaired the first meeting of the Cobra emergency committee. After being briefed by the head of Scotland Yard and the director of the security services, she branded it a ’barbaric case’, adding that 'there is a strong indication that it was an act of terrorism'. The Home Secretary added: 'This attack was an attack on everyone in the United Kingdom, and it will be condemned by people from every community. 'Our thoughts and prayers tonight are with the victim and his family. 'We have seen terrorism on the streets of Britain before, and have always stood firm against it. Despicable acts like these will not go unpunished.' Met commissioner Bernard Hogan Howe, Met Assistant Commissioner Cressida Dick, Defence Secretary Philip Hammond and London Mayor Boris Johnson and the intelligence services attended last night's Cobra meeting in Downing Street. Mr Cameron gave a press conference from the Élysée Palace before returning to London last night. He said: People across Britain, people in every community, I believe, will utterly condemn this attack. 'We have had these sorts of attacks before in our country and we never buckle in the face of them.' When news of the attack broke, he wrote on Twitter: 'The killing in Woolwich is truly shocking.' Ahead of tonight’s Cobra meeting Mr Johnson said: ’This afternoon’s attack in Woolwich is a sickening, deluded and unforgivable act of violence. ’My thoughts are with the victim and his family.’ He told reporters: 'I think it is very clear what happened tonight in Woolwich was a sickening and unforgivable act of violence, and I know thoughts of millions of Londoners and people around the country will be with the family of the victim tonight.  What we need to do is get the full facts.' Labour leader Ed Miliband said he is cutting short a visit to Germany to return to the UK. He said: 'This is a truly appalling murder which will shock the entire country. 'All of my thoughts are with the family and friends of the victim. The British people will be horrified by what has happened in Woolwich. They will be united in believing that this terror on our streets cannot be allowed to stand. 'The Labour Party will offer the Government our complete support in establishing the facts of what happened and ensuring that those responsible face the full force of British justice.' Other political leaders called for calm and warned against knee-jerk reactions to the killing. Earlier Mr Miliband said on Twitter: 'Shocked by appalling events in Woolwich. Whole country will be horrified by what has happened.' A statement from the Muslim Council of Britain said it understood the victim was a member of the Armed Forces. It said: 'This is a truly barbaric act that has no basis in Islam and we condemn this unreservedly. 'Our thoughts are with the victim and his family. 'We understand the victim is a serving member of the Armed Forces. Muslims have long served in this country's Armed Forces, proudly and with honour. 'This attack on a member of the Armed Forces is dishonourable, and no cause justifies this murder. ' 'This action will no doubt heighten tensions on the streets of the United Kingdom. 'We call on all our communities, Muslim and non-Muslim, to come together in solidarity to ensure the forces of hatred do not prevail.' UKIP leader Nigel Farage said: ’We are all left horrified by this appalling attack on the peaceful streets of London and our thoughts and prayers go out to the family of the young man who was killed and those who were injured. ’I hope and believe that this is an isolated incident and appeal for calm in our communities.’ Respect MP George Galloway was condemned by critics after writing on Twitter: 'This sickening atrocity in London is exactly what we are paying the same kind of people to do in Syria.' Leader of the far-Right BNP Nick Griffin claimed soldiers were 'safer on front line than in London, that's the reality of mass immigration', adding: 'The politicians who did this to Britain should hang.' Tory vice-chairman Michael Fabricant wrote on Twitter: ’I do hope members of the armed forces are not now advised to not wear uniforms in our streets for fear of terror attacks.’ Deputy Prime Minister Nick Clegg, who was briefed on the incident before the Cobra meeting, said: 'A shocking and horrifying attack. This afternoon witnessed a tragedy on the streets of our capital.' The Queen is said to be 'concerned' at the news of the attack and has asked to be kept up to date on the latest developments, Buckingham Palace said.