The parents of American aid worker Peter Kassig today released a YouTube video begging his ISIS captors to 'show mercy' and free him. Ed and Paula Kassig, from Indianapolis, made the emotional plea just one day after the 26-year-old war veteran was threatened with death in graphic footage filmed by the terrorist group. Referring to his son as Abdul-Rahman - a name he took having converted to Islam while imprisoned - Mr Kassig said: 'We implore his captors to show mercy and use their power to let our son go.' The school teacher, who was filmed on a sofa alongside his wife, continued: 'Our family deplores all human suffering and the loss of innocent life, no matter who is responsible. SCROLL DOWN FOR VIDEO . Emotional plea: Ed and Paula Kassig today released a YouTube video (pictured) begging ISIS to 'show mercy' and release their 26-year-old son Peter, who was threatened with death by the terrorist group yesterday . Aid worker: Peter Kassig (left), who has been held captive by ISIS for the past year, first went to the Middle East as a U.S. soldier before returning as a medical worker. Right, he is threatened by an ISIS militant . 'We respond by trying to persuade aid and assistance. Our son was living his life according to that same humanitarian call when he was taken captive. 'We know that the Syrians have suffered. We also believe violence is not the solution to the problems that trouble us all.' Speaking directly to her son, Mrs Kassig, who was donning a headscarf and clasping a photo of the aid worker in her hands, added: 'We are so very proud of you and the work you have done to bring humanitarian aid to the Syrian people. 'Our hearts ache for you to be granted your freedom so we can hug you again and then set you free to continue the life you have chosen, the life of service to those in greatest need.' Desperate: Mr Kassig, who works as a school teacher, said: 'Our family deplores all human suffering and the loss of innocent life, no matter who is responsible. We respond by trying to persuade aid and assistance' He added: 'We know that the Syrians have suffered. We also believe violence is not the solution to the problems that trouble us all. We implore his captors to show mercy and use their power to let our son go' Inspiration: Mr Kassig, who has been held captive by ISIS for the past year, first went to the Middle East as a U.S. soldier before returning as a medical worker to help victims of war (pictured) Peter Kassig, who has been held captive by ISIS for the past year, first went to the Middle East as a U.S. soldier before returning as a medical worker to help victims of war. While in Turkey, he founded SERA (Special Emergency Response and Assistance), a medically-oriented emergency relief group that serves refugee populations and internally displaced persons. It was while working on a project for SERA almost exactly a year ago, on October 1, 2013, when he was captured by members of ISIS as he headed to Deir Ezzor in eastern Syria. Yesterday, Mr Kassig was threatened with death in a chilling video showing the beheading of 47-year-old British aid worker Alan Henning. Humanitarian work: While in Turkey, he founded SERA (Special Emergency Response and Assistance), a medical emergency relief organization that serves refugee populations and internally displaced persons . Selfless: It was while working on a project for SERA almost exactly a year ago, on October 1, 2013, when he was captured by members of ISIS as he headed to to Deir Ezzor in eastern Syria . He was shown kneeling in the desert at the end of the footage, which saw a masked militant tell President Barack Obama that U.S. 'aerial bombardments' are putting them under strain. The militant added: 'It's only right we continue to strike the necks of your people.' Speaking of his son's achievements in today's YouTube video, Ed Kassig said: 'At an early age our son was inspired by his grandfather to do humanitarian work. 'When he saw the suffering of the Syrian people, he went to Turkey and founded an organisation to provide aid and assistance. Beheading: Yesterday, Mr Kassig was threatened with death in a video showing the beheading of 47-year-old British aid worker Alan Henning (pictured). He was seen kneeling in the sand at the end of the footage . 'He helped train 150 civilians in skills needed to provide medical aid to the people of Syria. This organisation gave food, cooking supplies, clothing and medicine to those in need. 'He grew to love and admire the Syrian people and felt at home there. Our son's journey culminated in him embracing Islam. Sadly, he was taken captive and is not free to continue his life's work serving the people of the region.' President: Barack Obama (pictured) has condemned the death of Mr Henning and urged that U.S. forces and its allies will bring his killers to justice . The  beheading of Mr Henning yesterday followed the murders of three other hostages in similar circumstance: U.S. journalists James Foley and Steven Sotloff and British aid worker David Haines. U.S. officials have confirmed that Mr Kassig is being held by Islamic State militants, but have declined to give any more details of his capture. The aid worker's family said in a statement yesterday that they had stayed silent about this news 'at the wish of those who have held their son.' They also revealed that their son had converted to Islam while being held hostage. Former hostages told the family that Kassig's new faith has given him comfort during his long captivity. Last night, President Obama strongly condemned the death of Mr Henning and urged that U.S. forces and its allies will bring his killers to justice. 'Mr Henning worked to help improve the lives of the Syrian people and his death is a great loss for them, for his family and the people of the United Kingdom,' the politican said in a statement. 'Standing together with our U.K. friends and allies, we will work to bring the perpetrators of Alan's murder - as well as the murders of Jim Foley, Steven Sotloff and David Haines - to justice.' The President added that the U.S. and other nations will continue to take action to 'degrade and ultimately destroy' the Islamic State group. ED KASSIG: 'My name is Ed Kassig and this is my wife Paula. I'm a school teacher and my wife is a nurse who works with refugees. Our son is Abdul-Rahman, formerly known as Peter. He disappeared on October 1 of last year near Raqqa, Syria. 'At an early age our son was inspired by his grandfather to do humanitarian work. When he saw the suffering of the Syrian people, he went to Turkey and founded an organisation to provide aid and assistance. 'He helped train 150 civilians in skills needed to provide medical aid to the people of Syria. This organisation gave food, cooking supplies, clothing and medicine to those in need. 'He grew to love and admire the Syrian people and felt at home there. Our son's journey culminated in him embracing Islam. 'Sadly, he was taken captive and is not free to continue his life's work serving the people of the region. 'The driving force in our family has always been to serve others. Our son comes from two long lines of teachers and humanitarian workers. 'Our family deplores all human suffering and the loss of innocent life, no matter who is responsible. We respond by trying to persuade aid and assistance. 'Our son was living his life according to that same humanitarian call when he was taken captive. We know that the Syrians have suffered. We also believe violence is not the solution to the problems that trouble us all. 'There is so much that is beyond our control. We've asked our Government to change its actions, but like our son, we have no more control over the U.S. Government than you have over the breaking of dawn. 'We implore his captors to show mercy and use their power to let our son go . PAULA KASSIG: 'Dear son, we hope that you will see this message from me and your father. We are so very proud of you and the work you have done to bring humanitarian aid to the Syrian people. 'We were grateful and relieved to have received your messages earlier this year. We know you were very worried about your friend who was taken with you. He was released and is well. Please know that we are all praying for you and your safe return. 'Most of all, know that we love you, and our hearts ache for you to be granted your freedom so we can hug you again and then set you free to continue the life you have chosen, the life of service to those in greatest need.' 'We implore those who are holding you to show mercy and to use their power to let you go.'
Peter Kassig, 26, threatened with death in video released by ISIS yesterday .
His parents Ed and Paula Kassig today made emotional plea via YouTube .
Asked ISIS captors to 'show mercy and use their power to let our son go'
Referred to son as Abdul-Rahman; name he took after converting to Islam .
Mr Kassig was captured by militants while working as aid worker in Syria .
He featured in graphic video showing beheading of hostage Alan Henning .
The parents of American aid worker Peter Kassig today released a YouTube video begging his ISIS captors to 'show mercy' and free him. Ed and Paula Kassig, from Indianapolis, made the emotional plea just one day after the 26-year-old war veteran was threatened with death in graphic footage filmed by the terrorist group. Referring to his son as Abdul-Rahman - a name he took having converted to Islam while imprisoned - Mr Kassig said: 'We implore his captors to show mercy and use their power to let our son go.' The school teacher, who was filmed on a sofa alongside his wife, continued: 'Our family deplores all human suffering and the loss of innocent life, no matter who is responsible. SCROLL DOWN FOR VIDEO . Emotional plea: Ed and Paula Kassig today released a YouTube video (pictured) begging ISIS to 'show mercy' and release their 26-year-old son Peter, who was threatened with death by the terrorist group yesterday . Aid worker: Peter Kassig (left), who has been held captive by ISIS for the past year, first went to the Middle East as a U.S. soldier before returning as a medical worker. Right, he is threatened by an ISIS militant . 'We respond by trying to persuade aid and assistance. Our son was living his life according to that same humanitarian call when he was taken captive. 'We know that the Syrians have suffered. We also believe violence is not the solution to the problems that trouble us all.' Speaking directly to her son, Mrs Kassig, who was donning a headscarf and clasping a photo of the aid worker in her hands, added: 'We are so very proud of you and the work you have done to bring humanitarian aid to the Syrian people. 'Our hearts ache for you to be granted your freedom so we can hug you again and then set you free to continue the life you have chosen, the life of service to those in greatest need.' Desperate: Mr Kassig, who works as a school teacher, said: 'Our family deplores all human suffering and the loss of innocent life, no matter who is responsible. We respond by trying to persuade aid and assistance' He added: 'We know that the Syrians have suffered. We also believe violence is not the solution to the problems that trouble us all. We implore his captors to show mercy and use their power to let our son go' Inspiration: Mr Kassig, who has been held captive by ISIS for the past year, first went to the Middle East as a U.S. soldier before returning as a medical worker to help victims of war (pictured) Peter Kassig, who has been held captive by ISIS for the past year, first went to the Middle East as a U.S. soldier before returning as a medical worker to help victims of war. While in Turkey, he founded SERA (Special Emergency Response and Assistance), a medically-oriented emergency relief group that serves refugee populations and internally displaced persons. It was while working on a project for SERA almost exactly a year ago, on October 1, 2013, when he was captured by members of ISIS as he headed to Deir Ezzor in eastern Syria. Yesterday, Mr Kassig was threatened with death in a chilling video showing the beheading of 47-year-old British aid worker Alan Henning. Humanitarian work: While in Turkey, he founded SERA (Special Emergency Response and Assistance), a medical emergency relief organization that serves refugee populations and internally displaced persons . Selfless: It was while working on a project for SERA almost exactly a year ago, on October 1, 2013, when he was captured by members of ISIS as he headed to to Deir Ezzor in eastern Syria . He was shown kneeling in the desert at the end of the footage, which saw a masked militant tell President Barack Obama that U.S. 'aerial bombardments' are putting them under strain. The militant added: 'It's only right we continue to strike the necks of your people.' Speaking of his son's achievements in today's YouTube video, Ed Kassig said: 'At an early age our son was inspired by his grandfather to do humanitarian work. 'When he saw the suffering of the Syrian people, he went to Turkey and founded an organisation to provide aid and assistance. Beheading: Yesterday, Mr Kassig was threatened with death in a video showing the beheading of 47-year-old British aid worker Alan Henning (pictured). He was seen kneeling in the sand at the end of the footage . 'He helped train 150 civilians in skills needed to provide medical aid to the people of Syria. This organisation gave food, cooking supplies, clothing and medicine to those in need. 'He grew to love and admire the Syrian people and felt at home there. Our son's journey culminated in him embracing Islam. Sadly, he was taken captive and is not free to continue his life's work serving the people of the region.' President: Barack Obama (pictured) has condemned the death of Mr Henning and urged that U.S. forces and its allies will bring his killers to justice . The  beheading of Mr Henning yesterday followed the murders of three other hostages in similar circumstance: U.S. journalists James Foley and Steven Sotloff and British aid worker David Haines. U.S. officials have confirmed that Mr Kassig is being held by Islamic State militants, but have declined to give any more details of his capture. The aid worker's family said in a statement yesterday that they had stayed silent about this news 'at the wish of those who have held their son.' They also revealed that their son had converted to Islam while being held hostage. Former hostages told the family that Kassig's new faith has given him comfort during his long captivity. Last night, President Obama strongly condemned the death of Mr Henning and urged that U.S. forces and its allies will bring his killers to justice. 'Mr Henning worked to help improve the lives of the Syrian people and his death is a great loss for them, for his family and the people of the United Kingdom,' the politican said in a statement. 'Standing together with our U.K. friends and allies, we will work to bring the perpetrators of Alan's murder - as well as the murders of Jim Foley, Steven Sotloff and David Haines - to justice.' The President added that the U.S. and other nations will continue to take action to 'degrade and ultimately destroy' the Islamic State group. ED KASSIG: 'My name is Ed Kassig and this is my wife Paula. I'm a school teacher and my wife is a nurse who works with refugees. Our son is Abdul-Rahman, formerly known as Peter. He disappeared on October 1 of last year near Raqqa, Syria. 'At an early age our son was inspired by his grandfather to do humanitarian work. When he saw the suffering of the Syrian people, he went to Turkey and founded an organisation to provide aid and assistance. 'He helped train 150 civilians in skills needed to provide medical aid to the people of Syria. This organisation gave food, cooking supplies, clothing and medicine to those in need. 'He grew to love and admire the Syrian people and felt at home there. Our son's journey culminated in him embracing Islam. 'Sadly, he was taken captive and is not free to continue his life's work serving the people of the region. 'The driving force in our family has always been to serve others. Our son comes from two long lines of teachers and humanitarian workers. 'Our family deplores all human suffering and the loss of innocent life, no matter who is responsible. We respond by trying to persuade aid and assistance. 'Our son was living his life according to that same humanitarian call when he was taken captive. We know that the Syrians have suffered. We also believe violence is not the solution to the problems that trouble us all. 'There is so much that is beyond our control. We've asked our Government to change its actions, but like our son, we have no more control over the U.S. Government than you have over the breaking of dawn. 'We implore his captors to show mercy and use their power to let our son go . PAULA KASSIG: 'Dear son, we hope that you will see this message from me and your father. We are so very proud of you and the work you have done to bring humanitarian aid to the Syrian people. 'We were grateful and relieved to have received your messages earlier this year. We know you were very worried about your friend who was taken with you. He was released and is well. Please know that we are all praying for you and your safe return. 'Most of all, know that we love you, and our hearts ache for you to be granted your freedom so we can hug you again and then set you free to continue the life you have chosen, the life of service to those in greatest need.' 'We implore those who are holding you to show mercy and to use their power to let you go.'
The parents of American aid worker Peter Kassig war veteran was threatened with death in graphic to his son as Abdul-Rahman - a name he took mercy and use their power to let our son go.' The Paula Kassig today released a YouTube video captors to show mercy and use their power to let Syria. Yesterday, Mr Kassig was threatened with of 47-year-old British aid worker Alan Henning. captured by members of ISIS as he headed to to threatened with death in a video showing the beheading of 47-year-old British aid worker Alan converted to Islam while being held hostage.