Do you know this terrorist? North American IS
Do you know this terrorist? North American ISScreenshot

Crowdsourcing may be the key to prosecuting foreign nationals fighting in Syria, the Federal Bureau of Investigations (FBI) revealed Tuesday, as it asked for the public's help identifying an Islamic State (ISIS) terrorist.

“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,” said Michael Steinbach, assistant director of the FBI’s Counter-terrorism Division. 

Specifically, the FBI is focused on one case: the identity of an ISIS terrorist with a North American accent featured in the terror group's first feature-length propaganda film, "Flames of War."

"In the video, a man whose face is obscured by a mask alternates seamlessly between English and Arabic in pro-ISIS pronouncements intended to appeal to a Western audience," the FBI stated on its website. "Dressed in desert camouflage and wearing a shoulder holster, the masked man can be seen standing in front of purported prisoners as they dig their own graves and then later presiding over their executions."

The man, who has a distinctive Middle America or Canadian accent, claims that the soldiers are Syrian Army troops who were based in the ISIS headquarters city of Raqqa. 

“We’re hoping that someone might recognize this individual and provide us with key pieces of information,” Steinbach said. “No piece of information is too small.” 

To that end, the FBI has set up a dedicated tip page on ISIS terrorists here

"Flames of War," a 55-minute propaganda feature film, debuted last month. The documentary-style film - shot in unusually high quality for a terror film - warns of an imminent direct conflict against America, and is narrated by the masked man. 

The FBI announcement follows a heightened offensive to stop the flow of foreign nationals to fight in Syria. Last month, it announced that it had identified another foreign national - "John of London" - but has yet to release his name. 

Some estimates claim that up to 75,000 foreign nationals may now have joined Syrian rebel groups. Earlier this month, however, the National Counterterrorism Center (NCTC) placed the official estimate at closer to 15,000 foreign nationals from 80 countries, with roughly 2,000 Europeans and over 100 Americans. 

Outrage and concern in America about ISIS has risen dramatically over the past month, after the cruel beheadings of four US and British journalists and aid workers and escalating threats from the terror organization.