Updated with correction, Sept. 3, 3:00 p.m.

ISIS has allegedly beheaded Steven Joel Sotloff, the American journalist who appeared in the terrorist group’s propaganda video of James Foley’s beheading two weeks ago. In the first video, the executioners threatened Sotloff would meet the same fate if the U.S. military did not comply with the terrorists’ demands.

The U.S. didn't. ISIS appears to have followed through.

The video was first obtained by SITE Intelligence Group (Search for International Terrorist Entities), also known as SITE Intel Group, a relatively under-the-radar yet apparently very powerful research body that monitors jihadist movements. The Bethesda, Maryland, organization has published a shortened version of the beheading video and published a transcript on its news site, which has been largely inaccessible since news of the beheading broke, likely due to an uptick in Web traffic.

A description of SITE Intelligence Group on its Facebook page says its blog, INSITE, focuses on “all dimensions of extremism in the 21st century:  jihadism, white supremacy movements, hacker threats and everything in between. … All articles posted to the blog are intended to elevate the discussion regarding extremist threats -- transcending the conversational buzz and shining light on the greater factors at stake.” Among its products for sale is SITE Monitoring Service, which provides its subscribers -- government and commercial entities -- “immediate and timely translations of the most important jihadist material published.”

SITE made the decision to publish the video of Sotloff’s beheading when numerous mainstream news outlets in possession of it declined to do so, likely influenced by the overwhelming negative public reaction to the sharing of video and still images of Foley’s beheading, which quickly and inescapably proliferated on social media before YouTube and Twitter removed them.  The authenticity of the video obtained by SITE Intel Group has yet to be explicitly confirmed, but the White House released a statement Tuesday afternoon expressing “deepest condolences” for the “brutal murder of an innocent American journalist.”

SITE Intelligence Group is an incarnation of the SITE Institute, founded in 2002 by former Investigative Project colleagues Rita Katz and Josh Devon. Katz remains the executive director of the SITE Intelligence Group. Her bio says she is fluent in Arabic and Hebrew, having been born in Iraq and educated in Tel Aviv. She has worked as a government consultant on terrorist operations and is the author of the 2003 book, “Terrorist Hunter: The Extraordinary Story of a Woman Who Went Undercover To Infiltrate the Radical Islamic Groups Operating in North America.” She is the subject of a 2006 New Yorker profile, which described a visit to SITE’s offices (the location of which, at the time, Katz demanded the magazine leave unnamed):

“Each day, Katz finds about a half-dozen items on the Arabic message boards that are worth distributing. Her researchers, who monitor English-language jihadist websites, often find a few more. Some are propaganda: videos taking responsibility for attacks, statements of intents to attack, announcements of allegiances or splits. … SITE tries to have the items translated and sent to subscribers within an hour and a half of their first appearance online.”

SITE Intel’s speedy distribution of items likely explains why numerous media outlets appeared to have obtained evidence of the beheading video, or the video itself, about the same time. SITE Intelligence Group did not immediately respond to an inquiry for more information.

The SITE Institute was credited in 2007 with obtaining and releasing the first video of Osama bin Laden in three years, the Washington Post reported.  The Post said SITE beat Al Qaeda’s own release of that particular video and shared it with government agencies and news media. The story said Katz “declined to comment on the methods used to obtain the footage” but told the Post she was first made aware of it via a jihadist message board.

IBTimes will update this story as more information becomes available.

An earlier version of this story and headline incorrectly identified SITE Intelligence Group as a nonprofit organization. SITE Intelligence Group appears to be a private, for-profit company.  The SITE Institute was a nonprofit organization.