Around 60 anti-war protesters have been kettled by some 500 police outside Downing Street in a demonstration calling for an end to Western military action in Afghanistan.
The protesters were attempting to block off Whitehall, which houses government departments, including the UK Ministry of Defence.
A large assembly against the conflict has been coordinated on 8 October 2011 by the Stop the War Coalition, which brings together labour movement organisations, peace activists, human rights and faith bodies, and a range of NGOs and community groups.
It coincides with the tenth anniversary of the NATO-led invasion and military occupation of Afghanistan, which has given way to an uncertain, militarily enforced democratic process - but only fitful progress for women, minorities and ordinary people in a country still threatened by warlordism, drugs, killings and a Taliban resurgence.
Musicians, actors, celebrities and MPs joined the 5,000 anti-war activists, who say the public want an end to a military intervention which has claimed thousands of lives and cost the UK alone close to £10 billion.
The war in Afghanistan is estimated to be costing Britain £12 million a day - money which demonstrators say would be better spent on development, education and alleviating poverty.
Former serving soldier Joe Genton declared: said: "In a recent poll 74 per cent of people said they wanted our troops out. What we have learned since 9/11 is the limit of our democracy. The war against Afghanistan was unpopular from the start, and completely unnecessary; yet we've been there for ten years despite all the public dissent."
Jemima Khan said that the war in Afghanistan had failed every test of legitimacy. Overall it had not improved the lives of women and others in the country, she suggested.
* A picture of the kettling: http://yfrog.com/oc9bgrj