The parents of Peter Kassig, the American aid worker who was killed by the Islamic State militant group, said his life was evidence that "one person can make a difference."
In a brief statement Monday, Paula and Ed Kassig remembered their 26-year-old son, who was seized in October 2013, as both a realist and an idealist.
"Our hearts are battered, but they will mend," Paula Kassig said. "The world is broken, but it will be healed in the end."
Ed Kassig added: "Please pray for Abdul-Rahman, or Pete if that's how you know him, at sunset this evening. Pray also for all people in Syria, in Iraq and around the world that are held against their will."
Kassig was a former Army Ranger who had returned to the region as an aid worker. He had converted to Islam while in captivity and had adopted the name Abdul-Rahman.
Ed Kassig asked for privacy so the family can "mourn, cry and, yes, forgive, and begin to heal."
The Kassigs, in a statement released Sunday, said they were "heartbroken" to learn of their son's death, which was announced in a video by the Islamic State.
In his final letter to his parents, Peter Kassig wrote: "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's friends gathered recently in Tripoli, Lebanon, to plead for his release.
"He was full of sympathy for people, and he had some useful skills," Dr. Ahmed Obeid told the Los Angeles Times. "He was very courageous. Maybe that was his undoing in the end."
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