A new video has emerged on at least one Islamist extremist site purporting to show the murder by beheading of a second American journalist, Steven Sotloff.

BREAKING: New video appears to show execution of Steven Sotloff, the 2nd American killed by a self-professed member of ISIS – @leeferran

— ABC News (@ABC) September 2, 2014

Islamic State video purports to show beheading of US hostage Steven Sotloff http://t.co/vzRQAulLxH

— BBC Breaking News (@BBCBreaking) September 2, 2014

BREAKING: ISIS on Tuesday released a video that appears to show the beheading of American journalist Steven Joel Sotloff.

— The Hill (@thehill) September 2, 2014

The reports are emerging so quickly that Josh Earnest could not provide any answers at the White House press briefing this morning:

White House says cannot confirm authenticity of video purported to show beheading of U.S. hostage Sotloff by Islamic State

— Reuters (@Reuters) September 2, 2014

In the video, ISIS names its next victim — a British hostage:

Islamic State video issues threat against British hostage it names as David Haines: SITE

— Reuters (@Reuters) September 2, 2014

That apparently is an attempt to warn the UK from allying with the US:

Video warns governments to back off "this evil alliance of America against the Islamic State": SITE

— Reuters (@Reuters) September 2, 2014

The New York Times ran a profile of Sotloff when the video of James Foley’s murder emerged:

Steven J. Sotloff, a 31-year-old freelance journalist, self-described “stand-up philosopher from Miami,” immersed himself in the tumult of the Middle East for years, repeatedly venturing into some of the most hazardous conflict zones. He reassured friends that he knew the risks as he wrote for publications that included Time magazine, The Christian Science Monitor and World Affairs Journal. …

Described by friends as selfless, Mr. Sotloff spent most of his life in Florida except when he attended a boarding high school, Kimball Union Academy in Meriden, N.H., where he apparently developed a penchant for reporting and writing. He coedited the student newspaper, The Kimball Union, graduated in 2002 and attended the University of Central Florida, where he played rugby, worked for the independent student newspaper, Central Florida Future, and expressed deep interest in travel to the Middle East.

He left after three years and, soon after, began to pursue journalism full-time.

“The guy lit up a room. He was always such a loyal, caring and good friend to us,” Josh Polsky, who shared a dormitory suite with Mr. Sotloff, said in a telephone interview. “If you needed to rely on anybody for anything he would drop everything on a dime for you or for anyone else.”

The video and its images will likely flood the Internet over the next few hours, pushed by ISIS’ social-media fronts and others. I won’t post those, although some of the news articles linked may have some contained within them.

Update: NBC has more on the sourcing:

The Islamic militant group ISIS has beheaded Steven Joel Sotloff, anAmerican freelance journalist who was abducted a year ago Syria, a jihadist monitoring organization said Tuesday.

The monitoring organization, SITE Intel Group, made the announcement on Twitter. It said that ISIS had also threatened to execute a British captive, David Cawthorne Haines.

Update: The Washington Post has more of the message, and speculates that the murderer may be the same one who killed Foley:

The unidentified militant in the latest video denounces the Obama administration, saying, “I’m back, Obama, and I’m back because of your arrogant foreign policy towards the Islamic State.” He cites recent U.S. airstrikes against the group in Iraq, and warns that “just as your missiles continue to strike our people, our knife will continue to strike the necks of your people.”

The militant speaks with a British accent, raising the possibility that the executioner is the same individual who killed Foley.

There may be more than one Briton among the hostage security detail, too. It would make sense to use English-speaking guards to listen in on conversations between the hostages, if they are being held together.

Update: Indeed:

Remember Steven Sotloff as hero for reporting #Syria atrocities. Latest is ISIS murdering him. http://t.co/7f6OwDoubH pic.twitter.com/XpDGMPVxjx

— Kenneth Roth (@KenRoth) September 2, 2014

Well put.

Update: The NYT reports on what Sotloff was forced to say:

In the latest video, Mr. Sotloff describes himself as “paying the price” for the Obama administration’s decision to strike ISIS targets in Iraq.

ISIS will be paying the price for this and many other atrocities. Hopefully, very soon and in full.