Whistleblower's leaked US files reveal state of Afghan war

The US military was last night confronted with the largest and potentially most explosive breach of its security in wartime, as the whistleblower website WikiLeaks published thousands of secret reports from the campaign in Afghanistan.

The documents, which were allegedly downloaded by a single intelligence analyst working in Iraq with high-level access to internal military and diplomatic communications, provide a patchwork of evidence on the progress of the war over six years to the end of 2009 and reveal that the Taliban insurgency is better armed and the US military's equipment less reliable than in the official picture sketched by the Pentagon's spin doctors.

The US government condemned the publication of the documents, which was preceded by summaries printed in newspapers in three different jurisdictions. WikiLeaks founder Julian Assange explained that it had coordinated publication with The New York Times, The Guardian in the UK and the German magazine Der Spiegel in order to frustrate any legal manoeuvres to block their release.

The security breach could not come at a more sensitive time, as the conflict in Afghanistan approaches its tenth year with ebbing popular support in the US, confusion over military strategy and turmoil at the top of the military. Last month was the deadliest for foreign troops in Afghanistan since 2001, with more than 100 killed, and the top US military officer warned yesterday of more casualties as violence mounts over the summer. The remarks by the Chairman of the Joint Chiefs of Staff, Mike Mullen, on a visit to the country, came as the Taliban said they were holding captive one of two US servicemen who strayed into insurgent territory, and that the other had been killed. Admiral Mullen said Washington's goal of turning the tide against the insurgency by year's end is within reach.

The newspapers given privileged access to the WikiLeaks material revealed that the Taliban have used heat-seeking missiles against coalition forces, when public statements from the Pentagon have suggested less sophisticated weaponry was involved. Drone aircraft used to survey the battlefield and strike targets in Afghanistan have crashed or collided, forcing American troops to undertake risky retrieval missions before the Taliban can claim the drone's weaponry, according to The New York Times.

The White House last night insisted that President Obama had been "very clear and candid" about the difficulties of the war. The administration spokesman also attacked WikiLeaks' decision to post the material online. "We strongly condemn the disclosure of classified information by individuals and organisations which puts the lives of the US and partner service members at risk and threatens our national security," he said.

The Pentagon has been aware of a serious security breach since at least April, when WikiLeaks went public with a video of US troops in an Apache helicopter in Baghdad laughing after killing a group of Iraqis, which included two Reuters journalists.

Earlier this month, the man accused of leaking the video was finally charged by US military investigators after being held for weeks in Kuwait. Private First Class Bradley Manning, a 22-year-old army intelligence analyst, was arrested after an American journalist and former hacker reportedly turned him in to the authorities. During their conversations the intelligence analyst allegedly boasted that he had been the original source of the Apache footage and had also handed WikiLeaks more than 260,000 classified documents from US embassies in the Middle East.

Key documents

*Secret "black" unit of special forces hunts down Taliban leaders with instructions to "kill or capture" without trial.

*The US covered up evidence that the Taliban have acquired deadly surface-to-air missiles, one of which is believed to have brought down a Chinook helicopter in 2007, killing seven soldiers and a British military photographer.

*The Nato coalition is increasingly using deadly Reaper drones to hunt and kill Taliban targets by remote control from a Nevada base.

*The Taliban has massively escalated its roadside bombing campaign, which has killed more than 2,000 civilians to date.