DUSHANBE, September 3, 2014, Asia-Plus -- The Islamic State (IS) militant group released a video on Tuesday purporting to show the beheading of a second American hostage, journalist Steven Sotloff, raising the stakes in its confrontation with Washington over U.S. air strikes in Iraq.

A masked figure in the video seen by Reuters also issued a threat against a British hostage, a man the group named as David Haines, and warned governments to back off “this evil alliance of America against the Islamic State.”

BBC reports that the video, entitled "A second message to America", is about two-and-a-half minutes long and was apparently recorded in a desert.

It shows a masked figure together with Mr Sotloff, who is dressed in an orange gown.  Mr. Sotloff reads out a text addressed to Mr. Obama saying: “You''ve spent billions of US taxpayers'' dollars and we have lost thousands of our troops in our previous fighting against the Islamic State, so where is the people''s interest in reigniting this war?”  The masked man, whose voice is similar to that of the man who appeared to carry out the beheading of James Foley, then describes the act he is about to commit as retribution for the US air strikes.  The video ends with the militant threatening to kill the British captive.

Reuters says that a statement released by Sotloff''s family through a spokesman indicated the family considered the video to be authentic.  

In Washington, the White House said it could not immediately confirm the authenticity of the Sotloff video. But several U.S. government sources said it appeared to be authentic.

Reuters reports that the White House said late on Tuesday that Obama was sending three top officials - Secretary of State John Kerry, Defense Secretary Chuck Hagel and counterterrorism adviser Lisa Monaco - to the Middle East “in the near-term to build a stronger regional partnership” against the Islamic State militants.

U.S. officials also said Obama ordered 350 more U.S. military personnel to protect the large American embassy in Baghdad, bringing up to about 820 the number of U.S. forces working to bolster diplomatic security in Iraq.

Sotloff, a 31-year-old freelance journalist from Florida, was kidnapped in Syria in August 2013.  Sotloff’s colleagues reportedly described him as a dedicated journalist and gifted writer who had filed in-depth reports from across the Middle East.  Sotloff had worked for Time magazine, Foreign Policy and the Christian Science Monitor , and reported from Egypt, Libya and Syria.

BBC security correspondent Frank Gardner says the second execution video from IS is significant, even though it was largely expected and dreaded.  It shows that the recent US air strikes which have halted IS''s lightning advance across northern Iraq are causing the organization real damage, upsetting its plans to extend by force its rule into Kurdistan.  Unable to hit back militarily against America''s jets, Islamic State has responded with a form of information warfare that it knows will horrify most people in the West, Mr. Gardner notes.

The United States resumed air strikes in Iraq in August for the first time since the pullout of U.S. troops in 2011.   The raids followed major gains by Islamic State, which has declared an Islamic Caliphate in areas it controls in Syria and Iraq.   The US reportedly launched more than 120 air strikes in Iraq in the last month, in an attempt to help Kurdish forces curb the advance of Islamic State militants and protect minorities threatened by them.