As Iran became more heavily involved in fighting ISIL (Islamic State in Iraq and the Levant) after 2014 illegal arms traders and many irregular groups were seen with Iranian weapons and ammo. Actually Iranian made weapons, especially Iranian copies of Russian Cold War era infantry and artillery arms and ammo had been sent to Syria and Lebanon with increasingly frequency since the 1990s. But in those cases the recipients (the Syrian military and the Hezbollah militia) understood the need to be discreet. By the late 1990s Iran began selling, usually to arms smugglers, unmarked ammo for these weapons as well as the more than 50 million clones of Russian type assault rifles and machine-guns that flooded Africa and Asia after the collapse of most communist states after 1989. This got so bad that in 2012 the UN asked Iran to stop sending unmarked ammo for these weapons to arms traders in Yemen, Somalia and elsewhere in Africa. The availability of all this cheap Iranian ammo was more a factor in continued violence than the many weapons available to use the stuff.
This was not the first time Iran has been asked about this because more and more Iranian weapons have been showing up in Africa. It 2013 it was proven that all or most of this unmarked AK-47 ammunition was, in fact, coming from Iran. In addition to ammo Iran also supplies bomb making materials, rockets, machine-guns, and mortars. Some of the weapons have been North Korean while others are Iranian made copies of Chinese designs (usually based on Russian originals). Recently (after 2014) Iran was discovered sending North Korean copies (the Type 73) of the Russian PKM machine-gun to pro-Iranian Shia militias in Iraq and Yemen. The Type 73 was a bad copy of the PKM and a decade later North Korea introduced the Type 82, a more faithful copy of the PKM and slowly began retiring the Type 73s. Apparently North Korea eventually found a way to smuggle thousands of the Type 73s out to Iran. The Type 73 was adequate but while over a million PKMs were built since the 1960s, fewer than 50,000 Type 73s were manufactured. North Korea apparently got very little for the retired ones because most potential customers preferred to pay two or three times as much for a Cold War surplus PKM.
Iran always denied it was involved in this arms smuggling and just keeps at it. In addition to supporting rebels and Islamic terrorist groups it favors, the arms are often for sale, not free. The Iranians want to be paid in dollars or euros and this money pays for needed items that have to be smuggled back into Iran because of the many trade embargoes against Iran (because of their nuclear weapons program and support of terrorism). The main recipients of these weapons are Shia tribal rebels and al Qaeda in Yemen, al Shabaab and al Qaeda in Somalia, Hamas in Gaza, and the government of Sudan. Many other arms dealers in the region are also customers.