U.S. officials have confirmed the authenticity of a gruesome video in which an ISIS terrorist beheaded American journalist James Foley.

Today, Foley's family emotionally spoke out about Jim, who they described as strong, courageous and compassionate, and called for mercy for others who have been captured by ISIS, including American journalist Steven Sotloff.

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"We're very proud of Jim. He was a courageous, fearless journalist, very compassionate American. Really the best of America," his mother said. "And he always hoped that he would come home. That was his hope. And he sustained all the others who were with him with that hope."

"Jim just could feel the prayers. He was strong, courageous, loving to the end. We just hardly recognize our little boy. He was just a hero."

His father added that they know from the video that his last words were wishing he had more time to see his family.

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Foley's family also had a message for his killers, begging for compassion and mercy for Sotloff and other innocent journalists.

"They never hurt anybody. They were trying to help," his father said. "And there is no reason for their slaughter."

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When asked why Jim, who was previously captured in Libya for 45 days in 2011, would return to a dangerous, war-torn area, his father explained, “Why do firemen keep going back into blazing homes? Because it’s their job. He felt this was his job. This was his passion. So, he was not crazy. He was motivated by what he thought was doing the right thing.”

Watch the clip above.

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