>> Islamic State is making its own weapons and ammunition on an industrial scale. Going well beyond improvised production, its sophistication matches a national military force. Investigators from Conflict Armament Research recently visited six facilities operated by the militants in eastern Mosul. Progress there has been slow and grueling. Elite Iraqi army troops have retaken just a quarter of the city.
This is just a small glimpse into the jihadi army's preparation.>> We may have only just scratched the surface in terms of weapon production, and there could be a lot more on the western side.>> The director of CAR, James Bevin, a former UN weapons inspector, says the militants have a standardized production across their self-start caliphate.
And you have to remember that this group is lead by former Iraqi military officers and intelligence officers. So when we look at for example the weapons and ammunition that they're manufacturing particularly in Mosul, they were branded. They were lot marked and they're marked with the data of manufacture and the IS logo.
It reinforces the fact that they are a growing concern. And they have branded weapons. They have a comprehensive bureaucracy as you might expect a national government to employ.>> Their report says the militants have a robust supply chain of raw materials from Turkey and they estimate IS produced tens of thousands of rockets and mortar rounds in the months leading up to the Mosul offensive.
The bomb and weapons makers are also highly skilled. Researchers even found marked exam papers as militants learned their trade. As the caliphate collapses, there are fears these skills will be used to spread terror beyond Iraq and Syria's borders.