It's so big that it has to be supported on two tripods and fires ammunition that's three times the size of standard rifle ammo.
An Isis terrorist has been photographed aiming a 10-foot long sniper rifle out of a flat window in Kobane.
The fearsome weapon fires 23mm calibre bullets, far larger than the standard size.
What sort of effect this gun would have remains open to debate, however, according to firearms expert David Dyson.
He told MailOnline: 'The problem with identifying the effect of this gun is firstly that we don't know for sure what the calibre is, although there wouldn't be a lot of point in building something like this if it wasn't of a significant calibre. Secondly, and probably of more importance, we don't know how well it is made: is the barrel accurately machined and rifled?
'The effect will also depend on the type of ammunition used. These rounds exist [23mm] fitted with high explosive incendiary or armour piercing incendiary projectiles.They will be effective against personnel and vehicles including lightly armoured ones.'
The picture emerged after a show of force from al Qaeda's Nusra Front, a rival group. They toured in a convoy around villages they said they had captured from Syrian rebels.
Dozens of pick-up trucks bristling with anti-aircraft guns and men armed with heavy machine guns drove through settlements in the southern countryside of Idlib.
Isis was formed by a merger of the Nusra Front and Al Qaeda in Iraq in 2013, but many in the former group rejected the move. By March 2014 over 3,000 fighters had been killed in clashes between the two sides.
Meanwhile, video journalist Jake Simkin has offered a rare glimpse inside Kobane's last remaining field hospital.
Most of Kobane's hospitals and clinics now lie in ruins. Only one is still working - but its location is kept secret for fear it could be targeted by the militants.
Inside the tiny field clinic, saving lives and dealing with horrifying wounds of war comes first, and concerns such as keeping operating rooms sterile and cleaning up after surgery are on the back burner.
Read more: http://www.dailymail.co.uk/news/article-2859301/ISIS-s-latest-killing-ma...
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