Yesterday, the FBI released a 1:17 minute clip of a 55-minute Islamic State propaganda film with the hopes of identifying an English-speaking militant. The terrorist, believed to be an American or a foreigner educated in the United States, wears a mask and alternates "seamlessly between English and Arabic" throughout the clip. Behind him, he claims that Syrian officers are digging their own graves before they are executed.
A transcript of the video provided by the FBI:
We’re here in the 17th Division military base just outside the city of Raqqa. And we’re here with the soldiers of Bashar. You can see them now digging their own graves in the very place where they were stationed. The very place where they were stationed terrorizing the Muslims in Raqqa.
... of Allah is going to be carried out on these same soldiers by the brothers of the Muhajarin al Ansar that captured them. And behind them you can see the officers’ residence filled with bullet holes and artillery shells from the Islamic State.
This is the end of every Musaidi Kaffar that we get a hold of. This is the end that they face.
That we abandoned the fronts and stopped fighting the kuffar to turn our guns toward the Muslims. They lie. By Allah, we are the harshest towards the kuffar.
And the flames of war are only beginning to intensify. By Allah, the fighting has just begun.
Because of the man's apparent connection to the States, the FBI believes that the general public will be able to aid in identifying him. "We need the public's assistance in identifying U.S. persons going to fight overseas with terrorist groups or who are returning home from fighting overseas," Michael Steinbach, assistant director of the FBI’s Counterterrorism Division, said in a statement.
Though his face is not shown (he covers everything except his eyes, similar to the British executioner in the recent ISIS beheading videos), the FBI believes his accent and voice may spark recognition from the public. "No piece of information is too small," said Steinbach.
The FBI has had some success with voice recognition, which was used to identify of the British executioner known as "Jihadi John," who was in the beheading videos of James Foley, Steven Sotloff, David Haines and Alan Henning. (John's real name has not been released publicly.) In the two most recent videos, that of Haines and Henning, the executioner's voice sounds digitally manipulated, likely an attempt to avoid further tracing.