A video that al-Qaida published online in January 2016 was supposed to show off the group's strength in Yemen. After all, the terrorist organization has systematically capitalized on the chaos of the civil war to firmly entrench itself on the southern tip of the Arabian peninsula. But the video also demonstrated just how well-armed the fighters are. They were seen brandishing various German-designed weapons — among them the G3 battle rifle, G36 assault rifle, MG3 machine gun and MG4 light machine gun — which are being produced under German arms producer Heckler & Koch's license in Saudi Arabia.

These weapons should have never come into the possession of terrorists. A documentary, commissioned by DW and produced by Jordan's Arab Reporters for Investigative Journalism group (ARIJ), shows how weapons like these and other European-made guns ended up in the hands of militants in Yemen.

International law explicitly defines who may legally purchase weapons. It also stipulates that guns may under no circumstances be passed on to third parties. Despite these laws, however, various militant groups in Yemen are now in possession of exactly such arms.

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Black market for European arms

How was this possible? Why is al-Qaida in possession of weapons designed by German gun manufacturers? Brigadier General Mohamed al-Mahmoudi, who commands government troops in the city of Taiz, says the weapons were initially issued to units fighting for President Abed Rabbo Mansur Hadi. The problem, however, is that these troops are paid very little and at irregular intervals. To make ends meet, some resort to selling weapons and ammunition. Which then end up, either directly or via third parties, in the hands of al-Qaida or other terrorist groups.

ARIJ contacted Heckler & Koch for comment but received no reply. Germany's Ministry for Economic Affairs stated that it was unaware of any reliable evidence proving German-made weapons are being used in Yemen and added that it takes any indications this may be happening extremely seriously.

Ahmed Himmiche, who coordinates a panel of experts on Yemen at the behest of the UN Security Council, says illicit arms deals are widespread in the country. He says there are fighters not under control of Yemen's government who "receive military support, including weapons, which then end up on the black market or in the hands of entities under sanction."

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Swiss grenades, Belgian guns

One of the jihadi groups is the Abu al-Abbas brigade, an al-Qaida partner organization. The brigade is also in possession of other weapons, such as the laser-guided rifle RPG-32, manufactured in Jordan in cooperation with a Russian company.

Countless videos are circulated on the internet, produced mainly by the warring factions themselves. The analysis of the weapons seen in the excerpts adds up to a kind of showcasing of European arms manufacturers: Arms and military equipment of the Belgian company FN Herstal or HG 85 hand grenades, developed by the Swiss military. While the Belgian government was not willing to grant an interview, the Swiss said it would check the information provided by ARIJ. Spanish-produced weapons can be seen being used in Yemen by unauthorized groups. Neither the Spanish manufacturers nor the government responded to ARIJ's request.

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The documentary reveals that many of the weapons were first circulated in Saudi Arabia or the United Arab Emirates (UAE) while others come from Iran. "These include drones and fuel for missiles," said Ahmed Himmich, an expert on behalf of the UN Security Council research team. "These were all bought by four or five countries and then exported to Iran."

In addition to Western European weapons, arms from southeastern European countries such as Serbia and Bulgaria also appear to make their way to Yemen. There's a simple reason for their proliferation, says Lawrence Marzouk, editor of the Balkan Investigative Reporting Network (BIRN): "If a weapon from the United Kingdom or the United States falls into the hands of a terrorist organization like ISIS, these countries have a major headache to deal with, but it is much less problematic for Serbia, Bulgaria or other Eastern European countries."

The documentary's conclusion made clear that the availability of European weapons is part of the reason deadly fighting continues in Yemen.

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