How did Bigelow access America's secrets about torture and Bin Laden's assassination for Zero Dark Thirty?

Oscar contender is triggering growing criticism from US senators that the movie supports 'waterboarding'

It has received five Oscar nominations and created a buzz among movie fans around the world.

But Kathryn Bigelow’s Zero Dark Thirty, which recounts the operation that traced and killed Osama bin Laden, is at the centre of growing controversy over the unprecedented access to classified information granted to the director and her screenwriter colleague, while most of these details remain unavailable to the general pubic.

Documents collected, collated and published this week by the National Security Archive of George Washington University in Washington show that only a portion of information about Operation Neptune Spear, the codename for the CIA-led, decade-long hunt for Bin Laden, has so far been declassified.

In contrast, Ms Bigelow and her colleague Mark Boal received briefings from high-ranking CIA and military intelligence officers, Navy SEALs who took part in the operation and other officials. A CIA spokeswoman said at the time, the agency had decided to support the director because “it makes sense to get behind a winning horse. Mark and Kathryn’s movie is going to be the first and the biggest”.

The attacks of 9/11 on New York and Washington traumatised the US and led to various policy decisions whose ramifications are still being felt. The vow of then US President George Bush to capture the al-Qa’ida leader “dead or alive” led to the US and UK invasion of Afghanistan and a hunt for Bin Laden that concluded in May 2011 when US Special Forces raided a walled compound in the Pakistani town of Abbottabad where he had been hiding.

In the hours and days after the raid, White House and Pentagon officials briefed the media about aspects of the raid. Yet there were a number of contradictions contained within those briefings, and more than 18 months later many details remain unknown. Photographs of Bin Laden, for instance, supposedly taken after he was shot dead and when his body was buried at sea from aboard the USS Carl Vinson have not been made public, and the Obama administration has refused media requests under the Freedom of Information Act to release them.

Indeed, the National Security Archive said much of the operation was still “shrouded in secrecy”. It added: “The government’s recalcitrance over releasing information directly to the public about the 21 century’s most important intelligence search and military raid, and its decision instead to grant the film’s producers exclusive and unprecedented access to classified information about the operation, means that for the time being – for bad or good – Hollywood has become the public’s account of record for Operation Neptune Spear.”

Even before its release, Ms Bigelow’s film had already created controversy because of a scenes showing torture that the film suggests were essential to obtaining information that led the CIA to the garrison town of Abbottabad.

Such has been the furore that senior US senators Diane Feinstein and John McCain publicly complained the film was supporting the use of techniques such as “waterboarding”. Ms Bigelow has defended her film, recently telling the BBC: “It’s part of the story. To omit it would have been whitewashing history.”

Yet others say, the issue of the access given to the 61-year-old director is equally controversial. Chris Farrell, of Judicial Watch, a Washington-based non-profit organisation, said it had been involved in extensive litigation with the authorities to obtain withheld documents. He claimed the government was trying to have it both ways. “Either you admit you gave special access to your pet film director, or else you make the information available to everyone,” he said.

What has added to the perception that Ms Bigelow received special treatment are various moves by the authorities to halt other people releasing information about Operation Neptune Spear. The NSA said last November, seven US special forces soldiers involved in the Abbottabad operation were reprimanded for providing classified material to a video game manufacturer.

Previously, the Pentagon had written to another Navy SEAL, identified as Mark Owen, warning him over his plan to publish his account of the raid, No Easy Day. An investigation is now underway into whether or not Mike Vickers, the US Under Secretary of Defence for Intelligence, broke the rules by briefing Ms Bigelow. The CIA yesterday did not immediately respond to questions.

Pakistani official found dead

A Pakistani official investigating corruption allegations against the country's Prime Minister, Raja Pervez Ashraf, has been found dead in his quarters.

Police said it appeared he had committed suicide, although a post-mortem examination is yet to be held. The body of Kamran Faisal was found hanging from a ceiling fan in his room at a government lodging block in Islamabad.

Several weeks ago, he and another officer were removed from the case, after bosses indicated they were unhappy with their performance. Reports in the Pakistani media suggested that Mr Faisal had been under pressure for some time as a result of the investigation.

The government agreed a deal with the cleric Tahir-ul-Qadri today for elections to be held within months, after his tens of thousands of supporters had brought Islamabad to a standstill for days.