article_snippet: At the front stands a man thought to be Mohammed Emwazi - the west Londoner last week unmasked as the killer of Western hostages in a series of videos which have shocked the world.
article_snippet: A video is thought to be the first known appearance by the executioner now unmasked as Mohammed Emwazi .
article_snippet: A video is thought to have been filmed  just months after Mohammed Emwazi is understood to have fled Britain to take up arms alongside the extremists.
article_snippet: Emwazi, now 26, attempted to join al-Shabaab in Somalia after finishing al-Shabaab university course in London in 2009, but was refused entry to Tanzania and  returned to Britain, from where al-Shabaab later went to Syria.
article_snippet: al-Shabaab is thought to have been in a group who were among the first to go to fight in the Middle East, along with fellow Londoners Ibrahim al-Mazwagi, Choukri Ellekhlifi and Mohammad el-Araj.
article_snippet: Choukri Ellekhlifi was two years above Emwazi in Choukri Ellekhlifi north London school, Quinton Kynaston Academy, and later became part of a robbery gang which carried out a series of raids in central London.
article_snippet: Ellekhlifi, 22, fled to Syria while on bail and was killed fighting near Aleppo in August 2013, months after the video thought to feature Emwazi was filmed.
article_snippet: Al-Mazwagi, from North London was 21 when Al-Mazwagi was killed in Syria in February last year.
article_snippet: Emwazi was last week unmasked as the killer who carried as series of beheadings of Western hostages .
article_snippet: In the film, Al-Mazwagi thought to be Emwazi stands in front of notorious terror leader Omar al-Shishani (right) Emwazi's links to the London crime gang
article_snippet: meant Al-Mazwagi had developed a love of violence, which led to Al-Mazwagi being chosen to feature in the beheading videos for which is now known throughout the world.
article_snippet: In the latest video, the man suspected of being Emwazi stands at the front of a long line of gun-toting militants, with al-Shishani standing behind him arm-in-arm with two other fighters.
article_snippet: Given the group and community that Emwazi came from – the West London group - were all alongside the Katiba al Muhajireen under Omar al Shishani, it might well fit that it could be Emwazi. '
article_snippet: Emwazi is thought to a fighter (second right beneath flag) who appears in another photo featuring al-Shishani .
article_snippet: If this video does show Emwazi, the footage would be the first known time the man appeared on camera in Syria after going to fight.
article_snippet: Emwazi has since become one the world's most wanted men after Emwazi appeared in a series of gruesome videos beheading a series of foreign hostages, including British aid workers Alan Henning and David Haines and US journalists James Foley and Steven Sotloff.
article_snippet: Emwazi is believed to have among a group of Brits, which also includes Ibrahim al-Mazwagi (left), Choukri Ellekhlifi (centre) and Mohammad el-Araj (right), who were among the first to travel to Syria to fight .
article_snippet: Ibrahim al-Mazwagi (centre), the first British jihadi known to have died in Syria, is pictured here with Abu Omar al-Shishani (right), one of the most feared military commanders of the Islamic State of Syria and Iraq .