Southern Afghanistan's largest city, Kandahar, is slipping back under Taliban control as overstretched US troops focus on clearing insurgents from the countryside, a potentially alarming setback for President Barack Obama's war strategy.
Afghan authorities promise a counteroffensive against the militants in Kandahar, a pledge that appears aimed primarily at boosting public morale after a devastating bombing killed 43 people on Tuesday.
Losing Kandahar, a city of nearly 1 million and the Taliban's former headquarters, would be a huge symbolic blow because it is effectively the capital of the ethnic Pashtun-dominated south, the main battlefield of the Afghan war.
It is difficult to measure the extent of Taliban control, and NATO officials publicly discount the possibility that Kandahar is about to fall to the militants.
Thousands of US and Canadian troops are deployed throughout the province and around the city, which includes a major NATO base. NATO officials say the US troop buildup in Afghanistan will enable them to send more troops into Kandahar.
"Because there's one bombing, it doesn't mean the situation is going down the tubes," said Maj Mario Couture, a spokesman for NATO in Kandahar province.