Steven Sotloff
Friends of Steven Sotloff took to Twitter to mourn him after the American journalist was beheaded by the Islamic State. Reuters

Steven Joel Sotloff, the American journalist beheaded by Islamic State militants in a chilling video released Tuesday, was also an Israeli citizen who feigned sickness to observe the Jewish fast of Yom Kippur while in captivity, it was revealed Wednesday. An Israeli magazine kept quiet about having run his work for fear of further endangering him. Sotloff, 31, was kidnapped last year by the Islamic State, the group formerly known as ISIS.

Paul Hirschson, a spokesman for the Israeli Foreign Ministry, confirmed on Twitter early Wednesday morning that Sotloff, 31, was an Israeli citizen. Sotloff was a native of Florida who attended a Jewish religious school in Miami. He pretended to be sick so he could fast for Yom Kippur, a fellow captive told an Israeli newspaper, according to NBC News. The Jerusalem Report magazine, which published some of his work, also kept its ties to Sotloff secret for fear that writing for an Israeli publication would put him in even more danger.

Sotloff was the second American journalist to be beheaded by ISIS. James Foley, a freelancer for the GlobalPost, was killed by ISIS last month in a similar video. A hooded, masked figure dressed all in black appears in both videos to kill Foley and Sotloff.

"I'm back, Obama, and I'm back because of your arrogant foreign policy towards the Islamic State,” the man says in the second video before killing Sotloff. He said Sotloff was beheaded in response to U.S. airstrikes in Iraq that targeted ISIS.