The report found that a large proportion of the terror group’s current military arsenal is made up of "weapons and equipment looted, captured or illicitly traded from poorly secured Iraqi military stocks."

Daesh has also had access to weapons from other sources through the capture or sale of Syrian military equipment supplied to armed groups that are fighting the government of President Bashar al-Assad in Syria. Turkey, the Persian Gulf States and the US are among the countries that have been providing these weapons, according to the report.

The prominent human rights group said that the quantity and range of Daesh arsenal "ultimately reflects decades of irresponsible arms transfers to Iraq and multiple failures by the US-led occupation administration to manage arms deliveries and stocks securely, as well as endemic corruption in Iraq itself."

“The consequences of reckless arms transfer to Iraq and Syria and their subsequent capture by ISIL must be a wake-up call to arms exporters around the world,” Patrick Wilcken, the report’s author told CNN on Wednesday.

He said even if Daesh is uprooted, other armed groups will take their place.

Since the Syrian conflict started in 2011, the US and its allies have been providing military and financial aid to the militants who are accused of widespread war crimes.

The US has on several occasions airdropped weapons for militants fighting the Assad government. Some of the weapons have ended up in the hands of the Daesh terrorists.

In September, militants with the so-called Division 30, who had just graduated from a US-led military training program in Turkey, handed over their weapons to the al-Qaeda-affiliated Jabhat al-Nusra in Syria; Press TV reported.

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