The family of ISIS hostage and U.S. aid worker Peter Kassig released a YouTube video Saturday asking his captors to show mercy and free him. Referring to him as Abdul-Rahman -- a first name his family says he took, having converted to Islam while being held hostage -- father Ed Kassig said: "We implore his captors to show mercy and use their power to let our son go." Peter Kassig, 26, first went to the Middle East as a U.S. soldier and returned as a medical worker, feeling compelled to help victims of war. His mother, Paula, addressed her son in the video: "We are so very proud of you and the work you have done to bring humanitarian aid to the Syrian people," she said.
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Ed and Paula Kassig urge ISIS to release their son
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Peter Kassig changed his first name to Abdul-Rahman when converting to Islam
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"We implore his captors to show mercy," his father says on videotaped message
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"Most of all, know that we love you," his mother says to son
Kassig was struck by the resilience of the @placeholder he met, by their ability to smile and somehow joke even in the darkest of circumstances.