 Story highlights American Peter Kassig, 26, helped treat wounded Syrians 
 
 He served in the U.S. military in Iraq but looked for a "game changer" after returning home 
 
 His parents in Indianapolis, Indiana, confirmed he'd been taken hostage 
 
 Kassig converted to Islam while being held hostage, family says 
 
 Peter Kassig first went to the Middle East as a U.S. soldier and returned as a medical worker, feeling compelled to help victims of war. The United Nations estimates that more than 2.5 million Syrians have fled their country since an uprising in March 2011 spiraled into civil war. Hide Caption 98 of 98 
 
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 Kassig's journey began when he joined the U.S. Army Rangers in 2006 and deployed to Iraq in 2007. Right now we have very little and so our operational scope is very small. In the two years that followed, he fell in love, got married and quickly divorced. So, on his spring break this year he packed his medical kit and flew into the Lebanese capital. After finishing the semester back in the United States, he returned to Lebanon, only this time with a plan. I would also like to be able to say that I was able to give something back to everyone who helped along the way. I designed Special Emergency Response and Assistance around a belief that there was a lot of room for improvement in terms of how humanitarian organizations interact with and cooperate with the populations that they serve. "I don't want to get on a political soap box, but at the same time we have to think about why as a country we choose to help certain people and not others. The truth is sometimes I really think I would like to do something else, but at the end of the day this work is really the only thing that I have found that gives my life both meaning and direction. Peter knows we are good people, who love joking and laughter. I certainly plan on continuing to try and serve those who are in need for as long as I live. This work is important for the message that it sends to people back home, that one of the best aspects of the American way of life is our ability to come together in the face of adversity and to stand beside those who might need a helping hand.
– In its latest execution video, ISIS threatened that its next victim would be an American aid worker named Peter Kassig. The 26-year-old is a former Army Ranger from Indiana who served in Iraq in 2007 before being honorably discharged for medical reasons, reports CNN. He enrolled at Butler University upon his return to the US, but traveled to Libya on his spring break to learn about the Syria crisis. "I wanted more of a challenge, more of a purpose," he told the network in a 2012 interview. Eventually, Kassig decided to stay full time to do humanitarian work and founded a relief group called the Special Emergency Response and Assistance, reports the Washington Post. In the last few years, he has been delivering food and medical supplies to refugees from the Syrian conflict. Kassig's parents today released a YouTube video pleading for his release. They refer to their son as "Abdul-Rahman, formerly known as Peter." The Kassigs have previously said that their son converted to Islam while in captivity. A few quotes from Kassig, from CNN and from an interview last year with Time: “This is real, and it’s scary stuff, and it’s sad what is happening to people here. People back home need to know about it, they need to know. Sometimes you gotta take a stand, you gotta draw a line somewhere.” "I am not a doctor. I am not a nurse. But I am a guy who can clean up bandages, help clean up patients, swap out bandages, help run IVs, make people's quality of life a little bit better. This is something for me that has meaning, that has purpose." "In five years, if I can look back on all of this and say that our organization is able to truly help people, that I was able so share a little bit of hope, and that I never stopped learning, then I will know this all stood for something."