(CNN) -- An American named Douglas McCain was killed last weekend in Syria, where he'd gone to fight as a jihadi, his uncle told CNN.
The uncle, Ken McCain, said the U.S. State Department told the family Monday about the death.
Douglas McCain converted from Christianity to Islam several years ago, according to his uncle.
The family wasn't alarmed by his conversion, but they became aware of Facebook posts sympathetic to ISIS, an Islamist militant group, when he traveled to what they believed to be Turkey.
The fact that Douglas McCain became a jihadi left his family "devastated" and "just as surprised as the country," Ken McCain said.
Ken McCain described the nephew he knew as "a good person, loved his family, loved his mother, loved his faith" -- the latter being a reference to the Christianity he practiced before his conversion.
CNN has not confirmed that McCain was fighting with ISIS as opposed to another extremist group in Syria. Defense Secretary Chuck Hagel has called ISIS, which claimed responsibility for the recent beheading of American journalist James Foley, "beyond just a terrorist group" and "beyond anything we have seen."
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