British Authorities Hope to Unmask New ‘Jihadi John’

Weekend video appears to show ISIS fighter shooting Syrians in the head.

"We are examining the content of the video," a British Home Office spokesman told ABC News today.

The jihadist reportedly could be Abu Rumaysah, a British national who was arrested in September 2014, skipped bail and fled to Syria. ABC News has not confirmed those media reports.

The video is an attempt to divert attention from their military failures in Iraq and their inability to take care of citizens in the areas they control, a British official told ABC News.

Investigators are also working to identify a young boy featured in the video wearing military fatigues and saying in English: "We are going to go kill the kaffir [non-believers] over there."

He is reportedly Isa Dare, the son of jihadi bride Grace "Khadija" Dare of Lewisham, southeast London. She had posted a picture on social media in July of Isa’s aiming an AK-47 automatic rifle. ABC News has not confirmed those media reports.

On a visit to east London today, Cameron responded to the video, saying, “It's desperate stuff from an organization that really does do the most utterly despicable and ghastly acts and people can see that again today.”

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