Taleban forces in southern Afghanistan have taken control of a town which British troops had pulled out of after a peace deal with local elders.
The British-brokered deal appears to have come to an end
Some local people said they were leaving the town, Musa Qala in Helmand province, for fear of bombing raids on the Taleban by Nato forces.
US commanders and diplomats had criticised the deal.
They said it had not been done with elders but with the Taleban themselves and was not the way to defeat them.
The BBC's Alastair Leithead in Kabul says the loss of Musa Qala to the Taleban is a blow to the strategy of establishing peace deals in Helmand.
It comes just days before the British hand over command of Nato forces to an American general.
The Musa Qala peace deal was a controversial change of tactics for British troops in Afghanistan.
It saw them pull out of the small Helmand town as part of an agreement with the elders, who said they would keep Taleban fighters out of the town centre and run security with their own auxiliary police unit.
There has been peace for a 142 days, a British spokesman said - but that appears to have come to an end.
The Helmand governor and local people told the BBC that the Taleban had moved in overnight, arrested some of the elders who opposed them and destroyed part of the government compound.
It was this compound that British troops defended from wave after wave of attack in the summer.