Masked jihadist aims al-Shabaab video at potential British recruits

His face is hidden, but his voice is familiar. The masked presenter has appeared on al-Shabaab's propaganda videos in the past, but never before have his glossy infomercials for Jihad been so directly aimed at potential recruits in Britain.

The masked jihadist, with an unmistakable London accent, makes a well-rehearsed argument about the evils of the "disbelievers who dominate our lives and our lands" before asking, "Where do you, the Muslim in the West, see yourself in this bigger struggle?"

Then, against the backdrop of sweeping shots of the London skyline, the narrator names ten militants - men with apparent links to Britain - who he says have all been killed in "armed struggle", becoming "martyrs".

He lists towns where he claims recruits have come from: London, Liverpool, Cardiff, Bristol and Birmingham.

He describes a militant called "Asmat" as "an Indian brother from London" who tried to go to Afghanistan before travelling to Somalia to fight.

He introduces a militant called "Talha", "a towering figure" from London's East End, who addresses the camera saying, "I call on you today - all the Muslim men in Britain, especially the city of Tower Hamlets".

Then, violent, computer-generated imagery is used to invite viewers to join al-Shabaab. We have decided not to broadcast or publish this portion of the video.

Aspects of this hour-long film, though shocking, are unsurprising. We are used to seeing highly-produced propaganda videos from al-Shabaab, and have heard many estimates of there being dozens of British fighters in its ranks.

But this is a chilling watch, nonetheless. It is new, compelling evidence of a British link to this growing militant group.

And perhaps the most pressing concern for our security services is not what those British militants might be doing abroad, but how they might use that knowledge if they return home.