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ISIS hostage's mom reaches out to militant leader on Twitter

INDIANAPOLIS - The mother of an American aid worker threatened with beheading in Syria reached out to the leader of the Islamic State of Iraq and Syria (ISIS) via Twitter in a new effort to secure her son's release.

The group captured Peter Kassig, who changed his name to Abdul-Rahman while in captivity, in Syria on Oct. 1, 2013. In a video released Friday, an ISIS militant threatened to kill Kassig following the beheading of British hostage Alan Henning.

Latest ISIS video purportedly shows the execution of Alan Henning

Kassig, 26, had researched the region and knew the dangers, but he believed the good he could accomplish through his relief organization outweighed the risk, his friends said Wednesday.

Nearly 300 people gathered Wednesday at Butler University in Indianapolis, where Kassig was a student from 2011 to 2012, to celebrate his work to help Syrians and pray for his release. Many wore white in a symbol of peace. One woman held a sign that read "A hero for peace."

Many members of the local Muslim community joined Kassig's parents in prayer as Hazem Bata, executive director of the Plainfield, Indiana-based Islamic Society of North America, quoted passages from the Quran and urged Kassig's captors to free him.

"Follow the religion you claim to hold so dear and have mercy on Abdul-Rahman," he said. "We ask that you send him back safely to his family."

Several of Kassig's friends told The Associated Press that he was always interested in helping people and was drawn to the Middle East after he was deployed to Iraq as an Army Ranger in 2007.

Peter Kassig, the American founder of the relief organization Special Emergency Response and Assistance (SERA) and Iraq War veteran in an undated photo. SERA

He was aware of the risks, said Todd Hill, who met Kassig in college after his medical discharge from the Army.

"He fully understood that this was a possibility and he accepted that, and I think that says a tremendous amount about the sort of person he is and to the kind of legacy he wants to create," Hill said.

In a tweet addressed to Abu Bakr al-Baghdadi posted at least nine times on Wednesday, Paula Kassig begged for news of her son's fate.

"I am an old woman, and Abdul Rahman is my only child. My husband and I are on our own, with no help from the government. We would like to talk to you. How can we reach you?" she said in the message. It wasn't clear if the Islamic State leader has responded to her tweet.

Kassig's parents have also posted a video message online beseeching the group to release him unharmed.

In a statement released to media earlier this week, Ed and Paula Kassig revealed that their son said in a June letter that he's afraid to die and is saddened by the pain his captivity must be causing his family.

"I am obviously pretty scared to die but the hardest part is not knowing, wondering, hoping, and wondering if I should even hope at all," Kassig said in the letter, according to his parents. "I am very sad that all this has happened and for what all of you back home are going through. If I do die, I figure that at least you and I can seek refuge and comfort in knowing that I went out as a result of trying to alleviate suffering and helping those in need."

Kassig founded Special Emergency Response and Assistance, or SERA, in Turkey. The group provides food, clothing, medical care and other aid to those affected by the Syrian conflict. According to the United Nations, some 3 million Syrians have fled their country, half of them children.

Hill and Joe Dages, who live in Louisville, Kentucky, told the AP that Kassig researched the region before traveling to the Middle East and that when they last saw him, in March last year, he was passionate about his work.

"He felt a need to stay up all day and all night and continue to help because people were dying all the time," Dages said. "He thought that maybe if I can just pour a little more of myself into this we can save a few more lives."

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