An ISIS hostage video of Kayla Mueller has been revealed – showing the murdered aid worker pleading for help from captivity.

Mueller is only seen from the chest up, wearing a green shirt and with her hair covered with a black hijab.

Clearly in distress, she says: ‘My name is Kayla Mueller. I need your help.

‘I’ve been here too long and I’ve been very sick and it’s it’s very terrifying here.’

The 10-second clip ends before she reveals where ‘here’ is – but Mueller was filmed for the proof-of-life video by ISIS militants in Syria which was handed to her parents by the FBI on August 20, 2013, ABC News reports.

‘You just go into almost a catatonic state, I think. You can’t even stand up,’ her father Carl Mueller told Brian Ross about his reaction to seeing his daughter in the video three years ago.

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An ISIS hostage video of Kayla Mueller has been revealed – showing the murdered aid worker pleading for help from captivity

Clearly in distress, she says in the 10-second clip: ‘My name is Kayla Mueller. I need your help'

In an interview to air on 20/20 on Friday, her mother Marsha also spoke of her heartbreak at seeing her daughter as a helpless hostage.

‘I saw how thin she looked but I saw that her eyes were very clear and steady,’ she said. ‘It broke my heart but I also saw her strength.’

Mueller, of Prescott, Arizona, and her boyfriend were abducted by ISIS gunmen from a Doctors Without Borders vehicle near a hospital in Aleppo run by the humanitarian group on August 4, 2013.

At the time, ISIS were not as widely known as they are now and sent the clip of Mueller, one of their first Western hostages, in a bid to secure a millions of dollars in ransom.

The 22-megabyte video was sent to a friend of the aid worker, who passed it on to authorities, who then handed it over to her parents.

Chris Voss, a retired hostage negotiator for the FBI, looked at the clip provided by ABC.

He said ISIS would have rehearsed and filmed this brief clip a number of times to get it right and put makeup on Mueller to make her appear in good health.

The Muellers (above) said they trusted non-governmental organizations 'like sheep'

Marsha and Carl Mueller (pictured in a video appeal to ISIS) said that although they got had the hostage video in August 2013, they didn't begin negotiations for 10 months

‘They want to put enough out there to start a negotiation. And that's what this is intended to do,’ he told ABC.

But although the video was received by the Muellers within weeks of their daughter’s capture, they didn’t begin negotiations for 10 months.

They pinned their hopes on the non-governmental aid groups their daughter had worked for, including the Danish Refugee Council, Support to Life and the NGO Forum.

They said the groups told them the government has stepped in to help and would bring their daughter home safe.

Carl Mueller told ABC that his family trusted them all ‘like sheep.’

They didn’t start negotiating for their daughter’s freedom until May 23, 2014 – which is when they say Doctors Without Borders finally handed over an email address from Mueller’s kidnappers which they had got from one of their own workers who had been held hostage and freed.

Days later, they received an audio clip with Kayla’s voice telling them that she remains healthy as well the price of her freedom.

‘I saw how thin she looked but I saw that her eyes were very clear and steady,’ Mueller's mother Marsha said. ‘It broke my heart but I also saw her strength’

Mueller is seen from the chest up, wearing a green shirt and with her hair covered with a hijab

The 22-megabyte video was sent to a friend of the aid worker, who passed it on to authorities, who then handed it over to her parents in August 2013

TIMELINE OF KAYLA MUELLER'S ABDUCTION AND AFTERMATH AUGUST 3, 2013: Doctors Without Borders said Kayla Mueller arrived at their hospital in Aleppo from southern Turkey at around 4pm with her boyfriend. Because Mueller and her boyfriend had arrived late in the day, he didn’t have time to finish his work – and were allowed to stay inside the compound that night because there were limited safe places to stay in the Industrial City neighborhood. AUGUST 4: Mueller’s boyfriend Omar Alkhani asked staff for help getting back to the city’s bus depot, who arranged for a hired car and driver to take them to the bus depot. All three occupants of the car were stopped and seized by armed men shortly after leaving the hospital. The driver was released an hour later. AUGUST 20: The FBI pass along a 10-second hostage video to Mueller’s parents, which had been emailed to a friend of hers. Sometime in August, Alkhani and an MSF worker were released. JANUARY 2014: Three women and two women who worked for MSF were abducted by ISIS. APRIL: The three women were released and later revealed they had been held in the same place as Mueller, who had asked them to smuggle a letter to her parents. They were also told by their captors to memorize an email address to later use to negotiate Mueller’s release. MSF passed along the letter and information, but decided to withhold the email address out of concern for the safety of the still-detained prisoners. MAY 14: Two male prisoners were released. MAY 23: Email address was handed over to the Muellers so hostage negotiations could begin. MSF apologized that Marsha Mueller had to reach out to them first for it. MAY 29: Mueller’s parents received an audio clip and their daughter told them that her kidnappers wanted Dr Aafia Siddiqui’s release in exchange for her and if not, then five million euros. Then, they heard what would be their daughter’s last spoken word to them: ‘Goodbye.’ SEPTEMBER 2014: Mueller was transferred along with two Kurdish women of Yazidi descent from an Islamic State prison to the custody of Abu Sayyaf, a former Islamic State minister for oil and gas. OCTOBER 2014: A Yazidi teenager who was held with Mueller who escaped in October said ISIS leader Abu Bakr al-Baghdad took Mueller as a 'wife', repeatedly raping her when he visited. FEBRUARY 6, 2015: Islamic State announce that Mueller was killed when Jordanian fighter jets bombed a building where she was being held, but Jordan expressed doubts about their account of her death. It remains unclear exactly how she died, but it is believed to be after an airstrike. Advertisement

She told them that her kidnappers wanted Dr Aafia Siddiqui’s release in exchange for her and if not, then five million euros.

Then, they heard what would be their daughter’s last spoken word to them: ‘Goodbye.’

Mueller had been held in captivity for 18 months, and kept as a sex slave in a Syrian dungeon until she was killed in an airstrike February last year.

The Muellers have said that Support to Life was helpful, but a small organization that couldn’t handle a hostage case.

But they blasted Doctors Without Borders for refusing to help negotiate for their daughter’s release – even though she was taken from a vehicle belonging to the charity.

Marsha and Carl Mueller said the group withheld vital information about their daughter they had gotten from freed hostages who worked for the organization.

The group has said it 'made a decision to share the email address at a later time out of concern for the safety of still-detained prisoners.'

Mueller, from Prescott, Arizona, is pictured with her family and pets as a youngster

'We regret the fact that Marsha Mueller had to reach out to us first before we did so; we should have reached out to the family first, and we have apologized to the Muellers for that,' the group has said.

The Muellers recorded a phone conversation, provided to ABC, with a senior official with MSF ten months after their daughter was kidnapped – asking the group for help with negotiations.

'No,' the official replied.

'The crisis management team that we have installed for our five people and that managed the case for our people will be closed down in the next week… because our case is closed.'

Mueller's father called Doctors Without Borders a 'fabulous organization and they do wonderful work'.

Doctors Without Borders refused to help negotiate for the release of Kayla Mueller (pictured) from her ISIS captors, her parents have said

'But somewhere in a boardroom, they decided to leave our daughter there to be tortured and raped and ultimately murdered.'

Doctors Without Borders (also known as Médecins Sans Frontières and MSF) called Mueller’s death a ‘terrible and tragic loss,’ but noted that their security policy forbids people from certain countries, including the US, from working at or even visiting the hospital.

They also said that they are not in a position to help with cases that don’t involve their own staff.

It added that staff at the hospital had no ideal that an American was going to turn up.

'She was not expected and no one at the hospital had any indication she was coming,' it said.

'If they had, they would have stated in no uncertain terms that she should not come, or cancelled the visit altogether,' the statement said.

'This was because Aleppo was well known to be a very dangerous place, a city at war (as it remains to this day), where the risk level for westerners, and Americans in particular, was very high.'

However, in a lengthy statement, the organization explained the decisions that were made following Mueller's abduction in August 2013.

Mueller was taken hostage with her boyfriend, Omar Alkhani (pictured together) in August 2013 after leaving a Doctors Without Borders hospital in Aleppo

KAYLA MUELLER'S PARENTS BLAST DOCTORS WITHOUT BORDERS Carl and Marsha Mueller blasted Doctors Without Borders for refusing to help negotiate for their daughter's freedom after she was kidnapped leaving one of their hospitals in Aleppo. The couple, of Prescott, Arizona, also accused the humanitarian group of withholding an email address which was needed to communicate with her ISIS captors in Syria. ‘Somewhere in a boardroom, they decided to leave our daughter there to be tortured and raped and ultimately murdered,’ Mueller’s father said in an interview with ABC News to air on Friday. The group admitted that it decided to share the email address at a later time ‘out of concern for the safety of still-detained prisoners.' But it also said it had no obligation to advocate for someone who did not work for the organization. They called Mueller’s death a ‘terrible and tragic loss’ – but added that they are 'an emergency medical organization. We are not hostage negotiators.' ‘In this instance, the Muellers asked MSF to actively intervene to help achieve Kayla’s release and we did not do so.’ The group said there are several reasons why and the ‘risks go beyond any one location.’ It said: ‘If MSF were generally considered by would-be abductors to be a negotiator of release for non-MSF staff, there is no doubt that this would increase the risk levels in many locations, put our field staff, medical projects, and patients in danger, and possibly force us to close projects where needs are often acute. ‘It would limit MSF’s ability to provide life-saving care to people caught in dangerous conflicts. ‘Furthermore, MSF is an emergency medical organization. We are not hostage negotiators.’ Advertisement

'As an organization that works in conflict zones and has had several of our colleagues and friends killed while trying to provide emergency assistance, we know this all too well.

'In this instance, the Muellers asked MSF to actively intervene to help achieve Kayla’s release and we did not do so.

‘There are several reasons for this: The risks go beyond any one location.

'If MSF were generally considered by would-be abductors to be a negotiator of release for non-MSF staff, there is no doubt that this would increase the risk levels in many locations, put our field staff, medical projects, and patients in danger, and possibly force us to close projects where needs are often acute.

‘It would limit MSF’s ability to provide life-saving care to people caught in dangerous conflicts.

'Furthermore, MSF is an emergency medical organization. We are not hostage negotiators.'

It added: 'There is risk inherent in humanitarian work in conflict, but we rely on people who are willing to take those risks to help us reach people in need around the world.

Mueller had been held in captivity for 18 months, and kept as a sex slave in a Syrian dungeon

'It’s awful to know that people like Kayla Mueller, who carried a very similar spirit into the world, died during efforts to reach some of those same people.'

Jason Cone, executive director of MSF-USA, added: 'From everything that I have learned from speaking with Kayla’s parents, Carl and Marsha, and from her passionate writing and advocacy about people in crisis, whether in Darfur, the Occupied Palestinian Territories, Tibet, or India, she exhibited the same incredible compassion and connection to neglected people that I see in my colleagues every day.

'All of us at MSF want to share our condolences and sympathies for the horrific experience that the Mueller family has lived through over the past three years. No one should have to endure such an experience.'

The group has had at least seven staff members taken hostage and released by ISIS – after they helped negotiate ransom payments for some.

But MSF said they had no moral obligation to help Mueller.

'We can't be in the position of negotiating for people who don't work for us,' Cone told ABC. 'I don't think there was a moral responsibility.'

Mueller was repeatedly forced to have sex with ISIS leader Abu Bakr al-Baghdadi (above)

Mueller was taken hostage with her boyfriend, Omar Alkhani, a Syrian national, in August 2013 after leaving a Doctors Without Borders hospital in Aleppo, where he had been hired to fix the internet service for the hospital.

She had begged him to let her tag along because she wanted to do relief work in the war-ravaged country.

Alkhani was released after two months, having been beaten.

Mueller was transferred in September 2014 along with two Kurdish women of Yazidi descent from an Islamic State prison to the custody of Abu Sayyaf, a former Islamic State minister for oil and gas, according to an FBI affidavit.

Sayyaf and his wife at times handcuffed the captives, kept them in locked rooms, dictated orders about their activities and movements, and showed them violent Islamic State propaganda videos.

Mueller, who would have turned 28 earlier this month, was also repeatedly forced to have sex with Abu Bakr al-Baghdadi, the leader of the terror group.

After her capture last year, Umm Sayyaf admitted she was responsible for Mueller's captivity while her husband traveled on Islamic State business.

She said that al-Baghdadi would occasionally stay at her home and that he 'owned' Mueller during those visits, which the FBI says was akin to slavery.

A Yazidi teenager who was held with Mueller and escaped in October 2014 said al-Baghdadi took Mueller as a 'wife', repeatedly raping her when he visited.