Nato launched its biggest offensive against the Taliban since the 2001 war today, targeting rebels and drug lords.
The assault in southern Helmand province, the opium heartland of the world's top producer came as the Taliban said they had captured a British spy, and hundreds protested in an eastern city over the killing of several civilians by US troops.
Maj-Gen Ton van Loon
Operation Achilles, which will eventually involve 4,500 Nato soldiers and 1,000 Afghans, began about dawn in Helmand.
"We consider this a major operation and I do not think you would be wrong if you were to characterise it as the start of ISAF's major operations for 2007," Colonel Tom Collins, spokesman for Nato's International Security Assistance Force (ISAF) told reporters in Kabul.
The Taliban over-ran the key Helmand town of Musa Qala a month ago, ending a controversial truce, but the alliance says the main aim of Achilles is to allow reconstruction.
"It signifies the beginning of a planned offensive to bring security to northern Helmand and set the conditions for meaningful development that will fundamentally improve the quality of life for Afghans in the area," ISAF southern command chief Major-General Ton van Loon said.
The open-ended operation is aimed largely at allowing the repair and expansion of the Kajaki dam hydroelectric facility. "Operations will focus on improving security in areas where Taliban extremists, narco-traffickers and other elements are trying to destabilise the government," Maj Gen van Loon said.
Nato said one of its soldiers had been killed in combat today, but did not give the nationality. More than 4,000 people died in fighting last year, the bloodiest since US-led forces ousted the Taliban in 2001.
The Nato offensive came as hundreds of people protested in the eastern city of Jalalabad, near Pakistan, over the killing of several civilians by US troops on Sunday. At least 2,000 people blocked the road between the city and Kabul, a major trade route to Pakistan, chanting "Death to Americans!", witnesses said.