NEW DELHI: Following the execution of British aid worker David Haines, a new video has surfaced showing an Islamic State militant beheading a second British aid worker -- Alan Henning. The same video shows the masked militant threatening to kill American hostage Peter Edward Kassig.

Henning is the fourth such execution, following David Haines and US journalists James Foley and Steven Sotloff. All four executions were recorded and circulated, showing a masked militant with a distinctly English accent standing beside the kneeling victims -- all dressed in orange jumpsuits.

The victims are made to make a statement linking their execution to their countries’ actions. “Hi, I’m Alan Henning. Because of our Parliament’s decision to attack the Islamic State, I as a member of the British public will now pay the price for that decision,” Henning says in the latest video.

Haines in his execution video addressed British Prime Minister David Cameron, whilst Foley and Sotloff address US President Barack Obama and link US airstrikes on IS militants for their execution.

Whilst the Foley and Sotloff videos began with footage of Obama, the Haines video begins with footage of Cameron speaking about the United Kingdom’s decision to arm Kurdish forces to fight IS. In the voiceover, the killer references US airstrikes in Iraq, specifically strikes that enabled the Iraqi forces to win back the key area around Haditha dam in Anbar province.

President Obama, whose administration and the US Senate recently approved a $10 million bounty for information leading to the arrest or conviction of people involved in the execution of the two American journalists, issued a statement that said that the US “strongly condemns the brutal murder” of Henning.

“Mr. Henning worked to help improve the lives of the Syrian people and his death is a great loss for them, for his family and the people of the United Kingdom,” he said. “Standing together with a broad coalition of allies and partners, we will continue taking decisive action to degrade and ultimately destroy ISIL.”

As per the video, Kassig -- a 26-year-old former US soldier who was deployed to Iraq back in 2007 -- is threatened to be the next victim. Additionally, the militants have asked for $6.6 million in ransom for an American hostage who was a humanitarian aid worker, whose identity has been kept secret at the request of family members. The militants, in addition to the ransom, have asked for the release of Aafia Siddiqui - convicted in 2010 for targeting US officials in Afghanistan.

IS militants have been rapidly gaining territory in Iraq, their advances resulting in a political crisis as pressure mounted on former Iraqi Prime Minister Nouri-al-Maliki, who is blamed for pursuing sectarian policies, to resign. Whilst Haider al-Ebadi was sworn in as the new Prime Minister and the world found their scapegoat, the IS advance shows no sign of letting up.

The militants are labelled Sunni militants, and their rise attributed to divisive policies by the Shia-dominated administration at the centre. Though sectarianism is certainly a factor, this is an oversimplification, especially as sectarianism was not a factor in Iraq prior to the US invasion of 2003. With the US supporting Shia ethno-political parties and propping them to power, a Sunni identity rooted in the context of victimhood, emerged in Iraq. The US support to Sunni militants fighting the Bashar-al-Assad regime in Syria, which includes IS, further facilitated the group’s rise.