Thousands of US marines and hundreds of Afghan troops moved into Taliban-dominated villages in southern Afghanistan today in the first major operation under Barack Obama's strategy to stabilise the country.
The offensive was launched shortly after 1am local time in Helmand province.
The Taliban stronghold, in the south of the country, is the world's largest opium poppy producing area.
The goal is to clear insurgents from the Helmand River valley before the Afghan presidential elections take place on 20 August.
The offensive – called Operation Khanjar, or Strike of the Sword – was described by officials as the largest and fastest-moving of the war's new phase, involving nearly 4,000 marines and 650 Afghan forces.