The US has confirmed that the video showing the beheading of American journalist Steven Sotloff by Islamic State militants is authentic.
Before the verification, the US had said the killing would be one of “sickening brutality”. His family said they were “grieving privately”.
UN Secretary General Ban Ki-moon called the murder a “despicable crime”.
Mr Sotloff, 31, had appeared in a video last month which showed fellow US journalist James Foley being killed.
Mr Sotloff was seized in Syria in 2013.