British hostage Linda Norgrove may have been killed by a grenade thrown by US rescuers, the prime minister said on Monday, but 48 hours earlier a different version of events was released, with her captors accused of causing the detonation that caused her death.
Here, a timeline reveals how the official version of events changed in such a short period of time.
Ms Norgrove, an aid worker from Lewis in the Western Isles, was taken captive along with three Afghan nationals on 26 September. Although the Afghans were freed on 2 October, the kidnappers kept Ms Norgrove captive.
As soon as she was taken, the UK's Cobra committee - which deals with emergencies - had assessed that Ms Norgrove's life was in "grave danger".
Afterwards, Foreign Secretary William Hague would say: "Linda's captors were assessed to be representatives of a local Salafist group allied to the local Kunar Taliban who had links higher up the Taliban chain of command to al-Qaeda and to other insurgent groups operating in the the Pakistan and Afghanistan border."
US forces were in charge of the rescue mission as they were in control of the terrain where she was being held. They were advised by British officials. Prime Minister David Cameron was being briefed twice daily by the Cobra committee about the situation.
On this day, Mr Hague would later add, it was believed that Ms Norgrove was possibly to be moved and given to those "further up the Taliban command chain" and so it was agreed the rescue mission could go ahead.
Although the special forces were able to find Ms Norgrove and shield 10 women and children from fighting, Ms Norgrove was killed.
Tribal elders and Afghanistan intelligence officials told the BBC they had pleaded to be given more time to negotiate with the captors but their requests had been refused.
Foreign Secretary William Hague officially confirmed that Ms Norgrove had been killed during a rescue mission by US forces.
At the time, he said the 36-year-old was "killed at the hands of her captors in the course of a rescue attempt".
He said: "Working with our Nato allies, we received information about where Linda was being held and we decided that, given the danger she was facing, her best chance of safe release was to act on that information."
He said everything had been done to rescue Ms Norgrove and added: "Responsibility for this tragic outcome rests squarely with the hostage takers.
"From the moment they took her, her life was under grave threat. Given who held her, and the danger she was in, we judged that Linda's best chance lay in attempting to rescue her."
David Cameron also released a statement, saying: "Decisions on operations to free hostages are always difficult. But where a British life is in danger, and where we and our allies can act, I believe it is right to try."
International Security Assistance Force (Isaf) commander Gen David Petraeus said Afghan and coalition forces had done everything in their power to rescue Ms Norgrove.
And on Sunday, Dominic Medley, a spokesman for the Nato-led Isaf force, said many people - including the Afghan government and their officials - had been involved in trying to get the aid worker out.
"The commander of Isaf told all the staff assembled in the morning meeting that it was a valiant and courageous effort by the forces to rescue Linda.
"And, of course you can imagine, the special forces with such a task only want one outcome and that is to save the hostage, who was killed in the end by her captors."
There were also reports circulating that Ms Norgrove had died after her captors detonated a "vest bomb".
The BBC was told by officials that US troops in Afghanistan were seconds from rescuing the hostage when she was killed by a vest bomb held or worn by a kidnapper, while other international media were also given the same information.
But on Monday morning, David Cameron was 45 minutes late for his first monthly Prime Ministerial news conference in Downing Street with a different version of events.
Mr Cameron said he had spoken to Gen Petraeus who had suggested Ms Norgrove's death may have resulted from a US grenade and not at her captors' hands.
"That evidence and subsequent interviews with the personnel involved suggest that Linda could have died as a result of a grenade detonated by the task force during the assault," he said.
He said a joint US and UK investigation into the circumstances of Ms Norgrove's death had been launched and added that he had already spoken to her family about the "deeply distressing" news.
But he continued to defend the rescue mission.
He said: "I am clear that the best chance of saving Linda's life was to go ahead, recognising that any operation was fraught with risk for all those involved and success was by no means guaranteed."
He added: "None of us can understand just how painful this must be for Linda's family.
"Also it is deeply regrettable, particularly for them, that the information published on Saturday is highly likely to have been incorrect.
"The statements were made in good faith and on the basis of the information that we received."
He added: "Obviously, we have to now have this investigation to find out exactly what happened and whether bad mistakes were made.
"It would have been quite unorthodox to overrule and insist on a particular set of forces to carry out an operation against the advice of extremely talented and professional commanders on the ground."
Later Isaf released a statement on its website about the investigation. It said: "Initial reports indicated the explosion was caused by a detonation triggered by one of the captors who was in close proximity to Linda Norgrove. Subsequent review of surveillance footage and discussions with members of the rescue team do not conclusively determine the cause of her death."
And on Monday afternoon, Foreign Secretary William Hague told the House of Commons: "Every indication we had over the weekend suggested that Linda had been killed by the explosion of a suicide vest worn by one of the captors.
"Earlier this morning Gen Petraeus contacted the prime minister's office to say that in the review of the rescue operation, new information had come to light about the circumstances surrounding her death."
He added: "On the basis of the information available to us, we had no doubt whatsoever that there was a continual and real threat to her life and no credible option for a negotiated release.
"Her colleagues were released on 2 October but at no stage was there any serious attempt made by those holding her."
The UK prime minister's office announced that a British coroner would oversee a post-mortem examination on Ms Norgrove as soon as her body has been repatriated.
Speaking at Prime Minister's Question Time, Mr Cameron said he had stressed to US President Barack Obama that it was "extremely important" there should be a joint US-UK investigation.
He said "the picture still is unclear" about what happened, but added: "It is an impossibly difficult decision to make about whether to launch a raid and try to free a hostage. In the end, we must all be clear: the responsibility for Linda's death lies with those cowardly, ruthless people who took her hostage in the first place."
Mr Cameron also paid tribute to her as a "dedicated professional doing a job she loved in a country she loved".
The Leader of the Opposition, Ed Miliband, added: "She died doing a simple job: trying to make the lives of people in Afghanistan better, a necessary part of any political settlement."
Mr Cameron said he would be meeting Gen Petraeus on Thursday to discuss the attempted rescue of Ms Norgrove.
Gen Petraeus said finding out how Ms Norgrove died was his "priority".
Downing Street reported his comments after he met Prime Minister David Cameron in London, during a pre-scheduled meeting.
And speaking at a news conference in Brussels, the US Defence Secretary Robert Gates said the Taliban put Ms Norgrove in harm's way when they kidnapped her.
"The death of this aid worker is a tragedy and we offer condolences to her family and friends," he said.
"But I think there's also an important point to be made here. Let's not forget who put her in harm's way, who kidnapped her and who kept her on a mountainside at 8,000 feet.
"So, this is a terrible tragedy but the Taliban bear the principal responsibility here."
Gen Petraeus told the audience at the Royal United Services Institute in London that he had spoken to Ms Norgrove's father and updated him on the progress of the investigation.
Gen Petraeus also said the new version of events only emerged when footage was removed from a hard drive which showed a "sharper image" of what had happened.
"From that, it was very clear there was a throw-in motion and an explosion followed that and a grenade had been deployed," he said.
He said he did not want to speculate on the investigation and added: "It was disturbing, clearly, not to have the correct facts the morning after the operation was conducted and to have those provided later after the task force commander conducted further examination including watching six different videos; six different platforms."
He said "the best operatives in the world" had risked their lives on the mission, and also revealed that a AC-130 helicopter gunship which had been in the area at the time had killed two of those believed to have been holding her.
It emerges that Ms Norgrove's 60-year-old father John has given a full interview to a US newspaper journalist, in which he paid tribute to his daughter.
He told Philadelphia Inquirer's columnist Trudy Rubin, that Ms Norgrove had lived a "short life and a full life".
In Rubin's column, which was published in the US on Thursday, Mr Norgrove is reported to have said: "[Linda] was never keen on hanging out with fellow foreigners but was attracted to knowing the local people.
"Her love was for people. She embraced the people and the wildness of Afghanistan."